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/tui.py

@@ -15,7 +15,6 @@ from __future__ import annotations
 import json
 import math
 import sqlite3
-import sys
 from datetime import date, datetime, timedelta, timezone
 from pathlib import Path
 from typing import Any, Callable, Dict, List, Optional
@@ -26,7 +25,7 @@ from rich.markup import escape
 from rich.text import Text
 from textual.app import App, ComposeResult
 from textual.binding import Binding
-from textual.containers import Container, Horizontal, VerticalScroll
+from textual.containers import Container, VerticalScroll
 from textual.screen import ModalScreen
 from textual.message import Message
 from textual.widget import Widget
@@ -56,7 +55,6 @@ from .projection import (
     ConfidenceState,
     ProjectionResult,
     ProjectionStage,
-    ScenarioRange,
     compute_projection,
     ladder_count_text,
     ladder_lines,
@@ -64,10 +62,10 @@ from .projection import (
 )
 from .status import (
     CADENCE_DEFAULT_S,
-    FRESH_THRESHOLD_S,
-    STALENESS_THRESHOLD_S,
+    FRESH_THRESHOLD_S,  # noqa: F401 -- re-exported; tests/test_acceptance_sweep.py asserts parity with status
+    STALENESS_THRESHOLD_S,  # noqa: F401 -- re-exported (see above)
     format_disclosures,
-    grade_freshness,
+    grade_freshness,  # noqa: F401 -- re-exported (see above)
     deliberate_pause_lines,
     read_status,
     _journalctl_hint,
@@ -75,7 +73,6 @@ from .status import (
 from .status_composition import (
     StatusComposition,
     render_status_tui,
-    STATUS_POLL_INTERVAL_S,
 )
 from .control import MONITOR_HELPER, MonitorError, run_monitor
 from .derive import _parse_ts