Vouch request: integrate comment-checker as built-in feature (#3741)

[niklasschaeffer]

What I'd like to contribute

I've built a first-party integration of @code-yeongyu/comment-checker (the native tree-sitter-powered comment checker behind pi-comment-checker) directly into @oh-my-pi/pi-coding-agent — as a built-in extension, not a plugin, configurable via the TUI settings panel.

The PR was auto-closed because I'm not vouched yet: #3741

The branch is ready on my fork (niklasschaeffer/oh-my-pi, branch feat/comment-checker) and can be reopened as soon as I'm vouched.

What it does

After write / edit / multiedit / apply_patch tool results, the comment-checker runs the native binary on the changed content. When it detects comments/docstrings (exit code 2), it appends the warning back into the tool result so the agent must react — same behavior as the upstream pi-comment-checker extension. A missing binary is a silent no-op.

It also includes omp-specific per-file edit-details extraction (perFileResults / files from edit tool details), a self-heal path that re-surfaces unfired warnings on session_compact, an above-editor warning widget + footer status line, and a /comment-checker slash command.

Design decisions

• Built-in module — registered as an inline ExtensionFactory via loadExtensionFromFactory in sdk.ts (same pattern as the existing autoresearch built-in), gated on the commentChecker.enabled setting. Lazy-loaded with await import("./comment-checker").
• • Default OFF — opt-in via the TUI settings panel (tools tab, "Comment Checker" group). Zero footprint for existing users on upgrade. A commentCheckerActive condition gates the sub-settings (custom --prompt).
• • @code-yeongyu/comment-checker as an optionalDependency — bun install pulls the platform binary automatically; if absent, the resolver returns undefined and the extension is a silent no-op. No PATH fallback needed for the common case.

Files (11 changed, +1237)

File	Change
src/comment-checker/core.ts	Request extraction from write/edit/multiedit/apply_patch + omp per-file edit details
src/comment-checker/cli.ts	Binary runner (timeout, truncation, Promise.withResolvers)
src/comment-checker/ui.ts	Above-editor widget + footer status formatting
src/comment-checker/index.ts	Extension factory: tool_result, session_start, session_compact handlers + /comment-checker command
src/config/settings-schema.ts	commentChecker.enabled (default false) + commentChecker.prompt (gated on commentCheckerActive)
src/modes/components/settings-defs.ts	commentCheckerActive condition
src/sdk.ts	Gated inline-extension registration
packages/coding-agent/package.json	@code-yeongyu/comment-checker optionalDependency
test/comment-checker/core.test.ts	10 unit tests
package.json, bun.lock	Catalog entry + lockfile

Verification

• tsgo typecheck: clean
• • biome check on all changed files: clean
• • 10 unit tests: all pass (bun test test/comment-checker/core.test.ts)
• • Binary smoke-tested: exit 2 with warning on // bad comment, exit 0 on clean code
    I'd be grateful for a vouch so this PR can be reopened and reviewed. Happy to iterate on the design if there's feedback before then.

[can1357]

vouched!