When repo is omitted, lists owner's repos then concurrently searches
each one (semaphore cap 5, 5s per-repo timeout). Merges and sorts
hits by score desc with deterministic tiebreak. Partial failures
tracked in partial_repos without aborting the whole fan-out.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Adds SearchCode to gitea.Client and code_search MCP tool for single-repo
code search via GET /api/v1/repos/{owner}/{repo}/search?type=code.
Fan-out placeholder returns ErrValidation (lands in 7.3).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>