Summary

• preserve the original SQLite write/dispatcher lease error when rollback also fails, instead of masking disk I/O failures with cannot rollback - no transaction is active
• reject writes on stale connections when the main DB path is missing, zero-byte, or structurally truncated/malformed before BEGIN IMMEDIATE
• treat zero-byte DBs with durable board-state markers and zero-task DBs with dependent Kanban rows as corrupt/inconsistent instead of silently reinitializing empty boards
• escape zero-byte backup-marker glob patterns for unusual explicit DB filenames

Test plan

• env -u HERMES_KANBAN_DB -u HERMES_KANBAN_BOARD -u HERMES_KANBAN_WORKSPACES_ROOT -u HERMES_KANBAN_TASK -u HERMES_KANBAN_WORKSPACE -u HERMES_KANBAN_RUN_ID -u HERMES_KANBAN_CLAIM_LOCK python -m pytest tests/hermes_cli/test_kanban_db.py -q (182 passed)
• env -u HERMES_KANBAN_DB -u HERMES_KANBAN_BOARD -u HERMES_KANBAN_WORKSPACES_ROOT -u HERMES_KANBAN_TASK -u HERMES_KANBAN_WORKSPACE -u HERMES_KANBAN_RUN_ID -u HERMES_KANBAN_CLAIM_LOCK python -m pytest tests/hermes_cli/test_kanban_db.py tests/hermes_cli/test_kanban_diagnostics.py tests/hermes_cli/test_kanban_db_init.py tests/hermes_cli/test_kanban_boards.py tests/hermes_cli/test_kanban_core_functionality.py tests/hermes_cli/test_kanban_cli.py tests/tools/test_kanban_tools.py -q (588 passed, 1 existing discord audioop deprecation warning)
• python -m ruff check .
• git diff --check and diff static scan clean
• independent Cody subagent review passed with no security concerns or blocking logic errors

Operational note

After review/merge, restart or roll out the Hermes gateway/dispatcher process so long-lived dispatcher instances pick up this code. Kanban child task t_8322370b tracks that operational rollout.