feat(tooling): add --help/-h to sqlite-query and sqlite-exec (#722)

Both wrappers previously silently treated --help as a SQL comment and
returned empty result JSON. They now intercept --help/-h before
delegating to the Python connector and print proper usage text with
the correct JSON key names (affected_rows, not rows_affected).

ticket, sprint, and decision already supported --help — no change.

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

tooling/db/sqlite-query

@@ -1,4 +1,15 @@
 #!/usr/bin/env bash
 # Run a SELECT query on the ticketing database. Whitelistable command.
 # Usage: sqlite-query "SELECT * FROM tickets WHERE status='in_progress'"
+if [ "$1" = "--help" ] || [ "$1" = "-h" ]; then
+  echo "Usage: sqlite-query <SQL>"
+  echo ""
+  echo "Run a SELECT query on the ticketing database."
+  echo "Output is JSON: {\"ok\": true, \"count\": N, \"rows\": [...]}"
+  echo ""
+  echo "Examples:"
+  echo "  sqlite-query \"SELECT id, title, status FROM tickets WHERE sprint_id=36\""
+  echo "  sqlite-query \"SELECT * FROM tickets WHERE assigned_to='stig'\""
+  exit 0
+fi
 exec python3 "$(dirname "$0")/sqlite_connector.py" query "$@"