docs: update actor validation docs to reflect event-based guard

Self-trigger guard now only blocks comment/review events, not all
events. Updated CLAUDE.md, docs/forgejo.md API table, and known
limitations section.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CLAUDE.md

@@ -57,7 +57,7 @@ All other `src/github/` modules work on Forgejo via Octokit REST as-is (permissi
 - `src/github/operations/comments/create-initial.ts` — Platform-aware spinner/URL format
 - `src/github/operations/comments/update-with-branch.ts` — Forgejo branch link in tracking comment
 - `src/github/operations/branch.ts` — Uses `repos.getBranch()` on Forgejo (Forgejo has `/git/refs` not `/git/ref`)
-- `src/github/validation/actor.ts` — Bot-type check skipped on Forgejo; self-trigger guard active
+- `src/github/validation/actor.ts` — Bot-type check skipped on Forgejo; self-trigger guard only blocks comment/review events (`issue_comment`, `issues`, `pull_request_review`, `pull_request_review_comment`). PR, workflow_dispatch, and schedule events pass through even when actor matches bot_name.
 - `src/entrypoints/update-comment-link.ts` — Forgejo PR compare URL (`expand=1` instead of `quick_pull=1`)
 - `src/mcp/install-mcp-server.ts` — Skips GitHub public MCP server on Forgejo