Feedback reference calendar event id truncation bug

Do not truncate calendar event IDs when passing them to tools or displaying them. The tool_list_calendar_events bug (:10 slice) caused every delete and update to 404, but the delete wrapper masked 404s as 'already_gone (idempotent success)' — so 6 operations silently no-opped while the bot reported success.

Why: Short IDs look like valid IDs but are not. Masking 404 as success is the second failure layer that hides the first. Combined, they produce confident false reports.

How to apply: Always pass and display FULL event IDs. Any calendar tool that truncates for display must keep the full ID in a separate field. Delete/update wrappers must distinguish 'deleted', 'already_gone', and 'not_found' and surface NOT FOUND explicitly rather than swallowing it. Verify-after-mutate: any 'Failed'/'NOT FOUND'/'ABORTED' response must be surfaced to the user, never claimed as success.

[auto-memory session 344183f4-2979-4892-acc0-d2914dc2ecf3, confidence 0.88, mode direct]