Ignore code in document blocks

## Description

Harper should ignore "code reference" in document blocks such as YARD (Ruby) and JSdoc (Javascript).

## Component

- Core grammar checking engine

## Use Cases

Here is an example of code being marked as invalid:


```
#
# Deletes old Relational Analytics data
#
# Any data older than the cutoff is deleted from the duckdb database
#
# @param cutoff [ActiveSupport::TimeWithZone] 3.years.ago.midnight by default
#
# @raise [RuntimeError] if no database file has been prepared.
# @raise [RuntimeError] if an unsupported revision is encountered.
#
# @return [Boolean]
```

## Implementation Ideas

- It should identify common code documentation blocks, such as YARD (Ruby) and JSdoc (Javascript).
- For YARD I think the identification could be as simple as: for any line starting with `# @`, ignore anything in brackets (`[]`)
- Ideally it should also ignore anything in backtics, such as "MyModel" in `# Calling into ``MyModel`` to resolve the actual user.`

Start with the core grammar checking engine and trace how document blocks are tokenized and checked. Compare the requested YARD and JSDoc cases, including bracketed and backticked code references; done means those references are ignored without suppressing ordinary prose grammar checks.

Written by the indexing model from the issue text.