Symptom

`codedb_search query=""` returns `isError:false` body `0 results for '':`. `max_results=-3` and `max_results=0` also silently succeed. Indistinguishable from a real query that legitimately had no hits — the agent thinks the search ran.

Failing tests

• `tests.test.issue-bug7: codedb_search rejects empty query`
• `tests.test.issue-bug7: codedb_search rejects negative max_results`

Fix

Validate `query.len > 0` and `max_results >= 1` at the top of `handleSearch`, return explicit error.

Labels

bug