docs: rename bot from claude-bot to claude in CI and docs

Update all runtime-relevant references to the Forgejo bot username
from 'claude-bot' to 'claude' following the bot account rename.

- .forgejo/workflows/claude.yml: bot_name input
- docs/forgejo.md: setup guide, examples, and inline references
- CLAUDE.md: bot identity description

Test fixtures and historical PRD files are left unchanged as they
use 'claude-bot' as arbitrary mock data or historical record.

Co-authored-by: vtmocanu <vtmocanu@users.noreply.github.com>

CLAUDE.md

@@ -47,7 +47,7 @@ This fork adds Forgejo support via a lean adapter pattern — only 4 genuinely d
 
 All other `src/github/` modules work on Forgejo via Octokit REST as-is (permissions, comments, branches, git config, context, formatter).
 
-**Bot identity on Forgejo**: A dedicated `claude-bot` user provides bot identity (like GitHub's `claude[bot]`). The `bot_id`, `bot_name`, and `bot_email` action inputs control git commit attribution. When `bot_email` is set, it overrides the default noreply email format — set it to the bot user's registered email so Forgejo links commits to the profile. See `docs/forgejo.md` for setup.
+**Bot identity on Forgejo**: A dedicated `claude` user provides bot identity (like GitHub's `claude[bot]`). The `bot_id`, `bot_name`, and `bot_email` action inputs control git commit attribution. When `bot_email` is set, it overrides the default noreply email format — set it to the bot user's registered email so Forgejo links commits to the profile. See `docs/forgejo.md` for setup.
 
 **Key integration points** (these files have platform branches and are merge-conflict surface):