lint: monitor current linting errors on tracks

This is just a tracking issue, so that I'm not posting it in gists or release PRs. Later, I suppose I could link a personal repo that runs `configlet lint` on a schedule on every track.

At the time of posting, here are the tracks where `configlet lint` exits with at least one error:

#### 05ab1e

```text
The value of `blurb` is a zero-length string:
./config.json

The `tags` array is empty:
./config.json

Missing file:
./docs/SNIPPET.txt
```

#### ada

```text
The value of `blurb` is a zero-length string:
./config.json

The `tags` array is empty:
./config.json

Missing file:
./docs/SNIPPET.txt
```

#### ballerina

```text
A `files.exemplar` value is `.meta/reference/%{snake_slug}.bal`, which is not a unique `files` entry:
./config.json

The `tags` array is empty:
./config.json

Missing file:
./exercises/practice/calculator-service/.docs/instructions.md

Missing file:
./exercises/practice/echo-service/.docs/instructions.md

Missing file:
./exercises/practice/greeting-service/.docs/instructions.md

Missing file:
./exercises/practice/hello-world-service/.docs/instructions.md

Missing file:
./exercises/practice/legacy-service-client/.docs/instructions.md

Missing file:
./exercises/practice/order-management/.docs/instructions.md

Missing file:
./exercises/practice/service-composition/.docs/instructions.md

Missing file:
./exercises/practice/service-invocation/.docs/instructions.md

The `blurb` key is missing:
./exercises/practice/calculator-service/.meta/config.json

The `blurb` key is missing:
./exercises/practice/echo-service/.meta/config.json

The `blurb` key is missing:
./exercises/practice/greeting-service/.meta/config.json

The `blurb` key is missing:
./exercises/practice/hello-world-service/.meta/config.json

The `blurb` key is missing:
./exercises/practice/legacy-service-client/.meta/config.json

The `files` array contains value `tests/legacy_service_client_test.bal` but `./exercises/practice/legacy-service-client/tests/legacy_service_client_test.bal` could not be found:
./exercises/practice/legacy-service-client/.meta/config.json

The `blurb` key is missing:
./exercises/practice/order-management/.meta/config.json

The `blurb` key is missing:
./exercises/practice/service-composition/.meta/config.json

The `blurb` key is missing:
./exercises/practice/service-invocation/.meta/config.json

Missing directory:
./exercises/shared/.docs
```

#### ceylon

```text
The value of `blurb` is a zero-length string:
./config.json

The `tags` array is empty:
./config.json

The `files` array contains value `source/Leap.ceylon` but `./exercises/practice/leap/source/Leap.ceylon` could not be found:
./exercises/practice/leap/.meta/config.json

The `files` array contains value `source/LeapTest.ceylon` but `./exercises/practice/leap/source/LeapTest.ceylon` could not be found:
./exercises/practice/leap/.meta/config.json

Missing directory:
./exercises/shared/.docs
```

#### coq

```text
The `tags` array is empty:
./config.json

Missing file:
./exercises/practice/tautology/.docs/instructions.md

The `files` array contains value `test.v` but `./exercises/practice/rna-transcription/test.v` could not be found:
./exercises/practice/rna-transcription/.meta/config.json

The `files` array contains value `test.v` but `./exercises/practice/tautology/test.v` could not be found:
./exercises/practice/tautology/.meta/config.json

Missing directory:
./exercises/shared/.docs
```

#### d

```text
A `files.test` value is `source/%{snake_slug}.d`, which is not a unique `files` entry:
./config.json
```

#### forth

```text
The value of `blurb` is a zero-length string:
./config.json

The `tags` array is empty:
./config.json

Missing file:
./docs/SNIPPET.txt
```

#### gleam

```text
Missing directory:
./exercises/shared/.docs
```

#### gnu-apl

```text
The value of `blurb` is a zero-length string:
./config.json

The `tags` array is empty:
./config.json

Missing file:
./docs/SNIPPET.txt
```

#### gnucobol

```text
The `tags` array is empty:
./config.json
```

#### groovy

```text
A `files.exemplar` value is `.meta/src/reference/groovy/%{pascal_slug}.groovy`, which is not a unique `files` entry:
./config.json
```

#### idris

```text
The value of `blurb` is a zero-length string:
./config.json

The `tags` array is empty:
./config.json
```

#### io

```text
The value of `blurb` is a zero-length string:
./config.json

The `tags` array is empty:
./config.json

Missing file:
./docs/SNIPPET.txt
```

#### j

```text
The `exercises.practice.difficulty` key is missing:
./config.json

The `exercises.practice.difficulty` key is missing:
./config.json

The `exercises.practice.difficulty` key is missing:
./config.json

The `exercises.practice.difficulty` key is missing:
./config.json

The `exercises.practice.difficulty` key is missing:
./config.json

The `exercises.practice.difficulty` key is missing:
./config.json

The `exercises.practice.difficulty` key is missing:
./config.json

The `tags` array is empty:
./config.json
```

#### julia

```text
The slug `leap` is used for both a Concept Exercise and a Practice Exercise, but must only appear once on the track:
./config.json

`./concepts` contains a directory named `arithmetic-operators`, which is not a `slug` in the concepts array. Please add the concept to that array:
./config.json

`./concepts` contains a directory named `boolean-expressions`, which is not a `slug` in the concepts array. Please add the concept to that array:
./config.json

`./concepts` contains a directory named `integer-equality`, which is not a `slug` in the concepts array. Please add the concept to that array:
./config.json

`./concepts` contains a directory named `iterator-protocol`, which is not a `slug` in the concepts array. Please add the concept to that array:
./config.json

`./concepts` contains a directory named `nothingness`, which is not a `slug` in the concepts array. Please add the concept to that array:
./config.json

`./concepts` contains a directory named `pairs`, which is not a `slug` in the concepts array. Please add the concept to that array:
./config.json

`./concepts` contains a directory named `vectors`, which is not a `slug` in the concepts array. Please add the concept to that array:
./config.json

Missing file:
./exercises/concept/annalyns-infiltration/.docs/hints.md

Missing file:
./exercises/concept/annalyns-infiltration/.docs/introduction.md

Missing file:
./exercises/concept/annalyns-infiltration2/.docs/hints.md

Missing file:
./exercises/concept/dnd-char/.docs/hints.md

Missing file:
./exercises/concept/emoji-times/.docs/introduction.md

Missing file:
./exercises/concept/exercism-matrix/.docs/hints.md

Missing file:
./exercises/concept/tech-palace/.docs/hints.md

Missing file:
./exercises/concept/vehicle-purchase/.docs/hints.md

Missing file:
./concepts/abstract-types/introduction.md

Missing file:
./concepts/composite-types/introduction.md

Missing file:
./concepts/constants/introduction.md

Missing file:
./concepts/matrices-concatenation/introduction.md

Missing file:
./concepts/matrices-indices/introduction.md

Missing file:
./concepts/matrices-iteration/introduction.md

Missing file:
./concepts/matrices-mutation/introduction.md

Missing file:
./concepts/methods/introduction.md

Missing file:
./concepts/nothingness/introduction.md

Missing file:
./concepts/symbols/introduction.md

The `authors` array is empty:
./concepts/abstract-types/.meta/config.json

The `authors` array is empty:
./concepts/arithmetic-operators/.meta/config.json

The `authors` array is empty:
./concepts/boolean-expressions/.meta/config.json

The `authors` array is empty:
./concepts/boolean-logic/.meta/config.json

The `authors` array is empty:
./concepts/composite-types/.meta/config.json

The `authors` array is empty:
./concepts/conditionals/.meta/config.json

The `authors` array is empty:
./concepts/constants/.meta/config.json

The `authors` array is empty:
./concepts/emoji-symbols/.meta/config.json

The `authors` array is empty:
./concepts/if-expressions/.meta/config.json

Missing file:
./concepts/integer-equality/.meta/config.json

Missing file:
./concepts/iterator-protocol/.meta/config.json

The `authors` array is empty:
./concepts/matrices-concatenation/.meta/config.json

The `authors` array is empty:
./concepts/matrices-indices/.meta/config.json

The `authors` array is empty:
./concepts/matrices-introduction/.meta/config.json

The `authors` array is empty:
./concepts/matrices-iteration/.meta/config.json

The `authors` array is empty:
./concepts/matrices-mutation/.meta/config.json

The `authors` array is empty:
./concepts/methods/.meta/config.json

The `authors` array is empty:
./concepts/multiple-dispatch/.meta/config.json

The `authors` array is empty:
./concepts/randomness/.meta/config.json

The `authors` array is empty:
./concepts/short-circuit-evaluation/.meta/config.json

The `authors` array is empty:
./concepts/symbols/.meta/config.json

The `authors` array is empty:
./concepts/ternary-operator/.meta/config.json

The `authors` array is empty:
./concepts/unicode-identifiers/.meta/config.json
```

#### kotlin

```text
`./concepts` contains a directory named `booleans`, which is not a `slug` in the concepts array. Please add the concept to that array:
./config.json
```

#### nix

```text
The value of `blurb` is a zero-length string:
./config.json

The `tags` array is empty:
./config.json

Missing file:
./docs/SNIPPET.txt
```

#### ocaml

```text
The value of `exercises.practice.difficulty` is 0, but it must be between 1 and 10 (inclusive):
./config.json
```

#### pharo-smalltalk

```text
A `files.exemplar` value is `.meta/solution/%{pascal_slug}.class.st`, which is not a unique `files` entry:
./config.json
```

#### plsql

```text
A `files.test` value is `ut_%{snake_slug}#.plsql`, which is not a unique `files` entry:
./config.json
```

#### pony

```text
The value of `blurb` is a zero-length string:
./config.json

The `tags` array is empty:
./config.json

Missing directory:
./exercises/shared/.docs
```

#### qsharp

```text
The `tags` array is empty:
./config.json
```

#### scala

```text
The value of `exercises.practice.difficulty` is 0, but it must be between 1 and 10 (inclusive):
./config.json

The value of `exercises.practice.difficulty` is 0, but it must be between 1 and 10 (inclusive):
./config.json

The value of `exercises.practice.difficulty` is 0, but it must be between 1 and 10 (inclusive):
./config.json

The value of `exercises.practice.difficulty` is 0, but it must be between 1 and 10 (inclusive):
./config.json
```

#### shen

```text
Missing file:
./docs/SNIPPET.txt
```

#### solidity

```text
The `tags` array is empty:
./config.json

Missing file:
./exercises/practice/token-transfer/.docs/instructions.md

The `blurb` key is missing:
./exercises/practice/token-transfer/.meta/config.json
```

#### system-verilog

```text
The value of `blurb` is a zero-length string:
./config.json

The `tags` array is empty:
./config.json

Missing file:
./docs/SNIPPET.txt
```

#### z3

```text
Warning: The following concepts exist in the `practices` array of a Practice Exercise in `./config.json`, but do not exist in the top-level `concepts` array
numbers
comparisons
conditionals
loops
strings

Warning: The Concept `numbers` appears 12 times in the `practices` arrays of user-facing Practice Exercises, but can only appear at most 10 times:
./config.json

Warning: The Concept `comparisons` appears 11 times in the `practices` arrays of user-facing Practice Exercises, but can only appear at most 10 times:
./config.json

Warning: The Concept `conditionals` appears 11 times in the `practices` arrays of user-facing Practice Exercises, but can only appear at most 10 times:
./config.json

Warning: The following concepts exist in the `prerequisites` array of a Practice Exercise in `./config.json`, but are not in the `concepts` array of any user-facing Concept Exercise
basics
intermediates

Warning: The following concepts exist in the `prerequisites` array of a Practice Exercise in `./config.json`, but do not exist in the top-level `concepts` array
intermediates

`./exercises/practice` contains a directory named `propositional-logic`, which is not a `slug` in the array of practice exercises. Please add the exercise to that array. If the exercise is not ready to be shown on the website, please set its `status` value to "wip":
./config.json
```

#### zig

```text
Warning: The following concepts exist in the `practices` array of a Practice Exercise in `./config.json`, but do not exist in the top-level `concepts` array
functions
slices
type-coercion
conditionals
optionals
error-sets
enums
arrays
builtin-functions
pointers
control-flow
bitwise-operations
methods
importing
structs
allocators
generics

Warning: The Concept `functions` appears 16 times in the `practices` arrays of user-facing Practice Exercises, but can only appear at most 10 times:
./config.json

Warning: The Concept `conditionals` appears 11 times in the `practices` arrays of user-facing Practice Exercises, but can only appear at most 10 times:
./config.json

Warning: The following concepts exist in the `prerequisites` array of a Practice Exercise in `./config.json`, but are not in the `concepts` array of any user-facing Concept Exercise
functions
conditionals
optionals
error-sets
slices
enums
arrays
builtin-functions
pointers
type-coercion
control-flow
bitwise-operations
methods
importing
structs
allocators
generics

Warning: The following concepts exist in the `prerequisites` array of a Practice Exercise in `./config.json`, but do not exist in the top-level `concepts` array
functions
conditionals
optionals
error-sets
slices
enums
arrays
builtin-functions
pointers
type-coercion
control-flow
bitwise-operations
methods
importing
structs
allocators
generics

Missing directory:
./exercises/shared/.docs
```