fix(shell): daemon-start and health-poll auth handling; policy panel freshness

Review follow-ups on the auth-status work:

- Both daemon-start paths classified an auth-rejected hub as "daemon
  dead" via healthy() and showed a start-failure dialog while the
  shell banner above correctly blamed the token. They now share
  daemonAnswers(): only an unreachable probe counts as down.
- An auth-rejected poll now re-reads ~/.chain/hub-auth-token and
  reconnects when the file changed, so a token fixed outside Studio
  (CLI, editor) heals the connection without a restart — previously
  the client kept the stale in-memory token forever and the banner's
  own advice could not work.
- An endpoint switch resets the failure streak, so a stale in-flight
  probe can no longer let the unreachable banner blame the new
  endpoint for the old one's misses.
- The auth-policy panel re-queries when the hub token is saved or
  cleared in the panel above (reloadTick), instead of keeping a
  stale admin-denied hint; it also renders the hub's new
  reload_required flag as a pending-reload warning (DE+EN).
- today-pipeline.md still documented ~/.fai/today after the rename;
  the FAB theme comment now states the both-themes intent.

flutter analyze clean; 71 tests green including four new ones.

Signed-off-by: flemming-it <stefan.a.flemming@googlemail.com>

lib/theme/theme.dart

@@ -265,9 +265,11 @@ class ChainTheme {
         ),
         margin: EdgeInsets.zero,
       ),
-      // Match FABs to the filled-button accent: Material 3 defaults
-      // them to primaryContainer, which reads as a washed-out tonal
-      // surface next to the sky-700 CTAs in the light theme.
+      // Match FABs to the filled-button accent in BOTH themes:
+      // Material 3 defaults them to primaryContainer, a tonal
+      // surface that reads washed-out next to the primary CTAs
+      // (visually verified light and dark; the dark FAB follows
+      // the dark filled buttons on purpose).
       floatingActionButtonTheme: FloatingActionButtonThemeData(
         backgroundColor: scheme.primary,
         foregroundColor: scheme.onPrimary,