feat(client): respect .gitignore + better exclude defaults (#145)

[pranaygp]

Summary

• Add a new cssPeek.respectGitignore setting (default true) that reads the workspace root .gitignore and merges its patterns into cssPeek.peekToExclude before calling Workspace.findFiles.
• Expand the default cssPeek.peekToExclude to also cover common build artifact directories: **/.git/**, **/dist/**, **/build/**, **/.next/**, **/out/**, **/coverage/**.
• Reads .gitignore via vscode.workspace.fs.readFile (no new Node fs dependency added on the client). Note: the extension as a whole does not yet declare virtual-workspace support — package.json still has capabilities.virtualWorkspaces.supported: false and the language server uses Node fs. This PR does not change that; it just keeps the new reader from being the blocker if/when the rest of the extension catches up.
• No new npm dependencies — a small line-based .gitignore -> glob converter lives in client/src/gitignore.ts.

Closes #145

Behavior

When cssPeek.respectGitignore is true:

1. The extension reads the .gitignore at the workspace root (if any).
2. Each non-empty, non-comment, non-negation line is converted to one or two VS Code globs (file + directory variants for bare names; directory-only when the line ends with /).
3. Those globs are deduped against cssPeek.peekToExclude and passed as the exclude pattern to Workspace.findFiles.

Known limitations / edge cases

The converter is small and dependency-free. It explicitly skips:

• Blank lines and comments (#...)
• Negation lines (!pattern) — skipped to avoid accidentally including files
• Patterns that reduce to empty after stripping a leading / or trailing /
• Nested .gitignore files in subdirectories (only the workspace root file is read)

Other unsupported gitignore constructs are NOT detected — they pass through verbatim and may produce wrong or best-effort matches:

• Character classes ([abc], [!a-z])
• Escape sequences (\#, \!, \ )
• ** placements where gitignore semantics differ from VS Code's glob semantics — common shapes (foo/**, **/foo) work, exotic ones may not

Users with complex ignore needs can set cssPeek.respectGitignore to false and manage cssPeek.peekToExclude directly.

Test plan

• yarn build — zero TS errors
• yarn test — 33 passing (8 new tests covering gitignoreLineToGlob + readGitignoreGlobs with a fixture .gitignore)
• yarn lint — clean
• Manual smoke: open a real project with dist/ containing a duplicate stylesheet and verify peek navigates to the source file, not the built copy

🤖 Generated with Claude Code

[Copilot]

Pull request overview

Adds support for merging workspace-root .gitignore patterns into the extension’s exclude globs so Workspace.findFiles is less likely to return build artifacts / ignored outputs when indexing stylesheets.

Changes:

• Added cssPeek.respectGitignore (default true) and merged .gitignore-derived globs into cssPeek.peekToExclude before searching.
• Expanded default cssPeek.peekToExclude to cover common artifact directories (dist/, build/, .next/, out/, coverage/, etc.).
• Introduced a small .gitignore line-to-VS Code glob converter with accompanying tests and a fixture .gitignore.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
client/src/extension.ts	Merges .gitignore-derived exclude globs into Workspace.findFiles exclude patterns when enabled.
client/src/gitignore.ts	Implements .gitignore line parsing and workspace-root .gitignore reading via vscode.workspace.fs.
package.json	Adds new configuration setting and expands default exclude patterns.
tests/src/gitignore.test.ts	Adds unit tests for conversion and .gitignore reading behavior.
tests/fixture/.gitignore	Adds a fixture .gitignore used by the new test suite.

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[pranaygp]

Good catch — fixed in 98aa492. I removed the virtual-workspace claim from the PR body and from the readGitignoreGlobs doc comment, and now explicitly note that capabilities.virtualWorkspaces.supported: false and the server's Node fs usage still gate full virtual-workspace support. The .gitignore reader uses vscode.workspace.fs so it isn't the blocker, but I'm not claiming the extension supports virtual workspaces today.

[pranaygp]

Fixed in 98aa492 (Option A — clarified the comment to match behavior). The doc now explicitly enumerates what's skipped (blank, comment, negation, empty-after-stripping) and explicitly states that unsupported constructs (character classes, escape sequences, exotic ** placements) are passed through verbatim and may produce wrong or best-effort matches. I kept the converter dependency-free rather than growing detect-and-warn logic; users with complex needs can disable cssPeek.respectGitignore and manage peekToExclude directly.