Summary

Fixes #30687.

Kanban command startup still auto-initializes the DB so fresh installs work, but that same path was unsafe for an existing board whose DB had been truncated or replaced with a schema-less SQLite file. In that case connect() could create the full schema and let commands continue against an empty board.

This change adds a DB-open guard before schema creation:

• existing zero-byte Kanban DBs fail with a clear error instead of being initialized
• existing SQLite files that are missing the required tasks table fail before CREATE TABLE IF NOT EXISTS
• known named boards whose DB path is missing fail during automatic command startup
• hermes kanban init and create_board() pass an explicit allow_recreate flag, so deliberate initialization still works

The check also catches the risky alternate/top-level DB case: an existing current board plus an empty HERMES_KANBAN_DB target no longer becomes a new empty board by accident.

Tests

• scripts/run_tests.sh tests/hermes_cli/test_kanban_db.py tests/hermes_cli/test_kanban_boards.py
  • 221 passed
• /Users/dejain/nvidia/oss/hermes-agent/.venv/bin/ruff check hermes_cli/kanban.py hermes_cli/kanban_db.py tests/hermes_cli/test_kanban_db.py tests/hermes_cli/test_kanban_boards.py
  • passed

Notes

• Platform tested: macOS local dev environment.
• This does not attempt SQLite page recovery or backups; it only prevents the silent auto-recreation path and leaves explicit recovery/init decisions to the user.