chore: ignore .codeiq cache and graph artifacts

.codeiq/ holds a local code-intelligence cache (.mv.db) and a neo4j
graph store rebuilt on demand by the codeiq tool. Without this rule,
the auto-checkpoint hook captured several MB of binary blobs into
'pre-yolo' snapshot commits — clean up the working tree and prevent
future contamination.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: aksOps

.gitignore

@@ -23,3 +23,6 @@ docs/
 
 # Subagent worktree scratch paths (managed by the harness, not source)
 .claude/worktrees/
+
+# Local code-intelligence cache (codeiq) — runtime DB + neo4j store, not source
+.codeiq/