Merge origin/main into main

Reconcile the staged-projection and Diagnostics feature work with the CI
quality-gate changes from origin/main. The origin side of every conflict was
lint-only, so the feature imports were kept and the ruff fixes re-applied:

- keep the branch's added imports (timefmt, activity_readout, projection
  ladder helpers) and drop the unused ones ruff reported
- restore `noqa: E402` on the post-bootstrap imports in fenris-monitor and
  keep the `noqa: F401` re-exports in the TUI that tests assert on
- make the TUI monitoring-glyph test clock-relative instead of pinned to a
  fixed date

tests/test_issue_92.py

@@ -10,7 +10,6 @@ Covers:
 - AC92-7: Keyboard actions verified from normal launch with headless driver
 - AC92-8: Equivalent clickable actions at 80x24 and constrained widths
 """
-import sqlite3
 from datetime import datetime, timedelta, timezone
 from pathlib import Path
 from unittest.mock import patch
@@ -111,7 +110,6 @@ def _make_app(tmp_path, clock=None):
     """
     if clock is None:
         clock = _clock()
-    from unittest.mock import patch
     import fenris.tui as tui_mod
     from datetime import datetime as _real_datetime