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

src/fenris/status.py

@@ -15,8 +15,7 @@ Criteria: LC-9, CI-2, CI-4, FL-4, FL-5, FL-7.
 """
 import sqlite3
 from contextlib import contextmanager
-import sys
-from datetime import datetime, timedelta, timezone
+from datetime import datetime, timezone
 from pathlib import Path
 from typing import Any, Dict, Iterator, List, Optional, Tuple, TYPE_CHECKING
 
@@ -24,7 +23,7 @@ if TYPE_CHECKING:
     from .status_composition import StatusComposition
 
 from .projection import (
-    compute_projection, ConfidenceState, DISCLOSURES, ProjectionStage, ladder_count_text,
+    compute_projection, DISCLOSURES, ProjectionStage, ladder_count_text,
     ladder_lines, write_rate_gb_day,
 )
 from .store import SCHEMA_VERSION