Git LFS mismatch for shadcn-components.tar.gz breaks submodule usage

## Problem

`skills/web-artifacts-builder/scripts/shadcn-components.tar.gz` was committed as a raw binary blob, but `.gitattributes` tracks `*.tar.gz` with the LFS filter. This causes a persistent dirty working tree — every checkout produces a file that doesn't match the index.

```
$ git reset --hard HEAD
Encountered 1 file that should have been a pointer, but wasn't:
skills/web-artifacts-builder/scripts/shadcn-components.tar.gz

$ git diff --stat
.../scripts/shadcn-components.tar.gz | Bin 19967 -> 130 bytes
1 file changed, 0 insertions(+), 0 deletions(-)
```

## Impact

When this repo is used as a git submodule, `git pull --rebase` in the parent repo fails:

```
fatal: cannot rebase with locally recorded submodule modifications
```

There is no way to make the submodule clean without working around the LFS configuration.

## Workaround

Override `.gitattributes` locally inside the submodule:

```
echo '*.tar.gz filter= diff= merge=' > .git/info/attributes
git reset --hard HEAD
```

## Suggested fix

Either:
1. Re-commit the file through the LFS filter so the blob is a proper LFS pointer, or
2. Remove `*.tar.gz` from the LFS tracking in `.gitattributes` if LFS isn't intended for this file

The file was introduced in b0cbd3d (2026-03-06).