feat(player): polish sleep-timer UI — circular ring + in-button countdown (#272)

Replaces the text-pill schedule badge with a circular SVG progress ring
around the play/pause button. Accent→lavender gradient stroke, counter-
clockwise depletion synced to the armed deadline, subtle accent glow.

While a timer is armed, the Play/Pause icon inside the button is
swapped for a two-line stack: a small Moon (sleep timer) or Sunrise
(delayed start) glyph above the countdown (m:ss / h:mm:ss). The icon
is the mode marker so the ring can stay unified with the rest of the
app's accent palette.

Redesigns the schedule modal with a mood-tinted header (Moon for
"Pause after", Sunrise for "Start after"), soft radial accent glow in
the background, slide-up open animation. Circular glass close-button
scoped to this modal, with hover rotation + focus ring. Custom-minutes
field gains an inline "min" suffix. A live preview line at the bottom
shows when the action fires ("Pauses at 23:47" / "Starts at 23:47"),
updating as the user hovers a preset or types. Chips gain a small
hover lift plus accent-coloured shadow.

Also fixes a pre-existing duplicate-tooltip on the play/pause button:
title= attributes removed alongside the data-tooltip (title violates
the project's "never native tooltips" rule, so both showed at once).

Adds scheduledPauseStartMs / scheduledResumeStartMs to the player
store so the progress ring has a total-duration baseline, set and
cleared alongside the existing deadline fields.

New usePlaybackScheduleRemaining hook wraps the store subscription
and 500 ms tick into a single hook used by all three player views
(PlayerBar / FullscreenPlayer / MobilePlayerView).

i18n: delayPreviewPause / delayPreviewStart keys across all 8 locales.

Co-authored-by: Psychotoxical <dev@psysonic.app>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/MobilePlayerView.tsx

@@ -4,6 +4,7 @@ import { useTranslation } from 'react-i18next';
 import {
   ChevronDown, Play, Pause, SkipBack, SkipForward,
   Shuffle, Repeat, Repeat1, Heart, Music, MicVocal, ListMusic, X,
+  Moon, Sunrise,
 } from 'lucide-react';
 import { usePlayerStore, Track } from '../store/playerStore';
 import { buildCoverArtUrl, coverArtCacheKey, star, unstar } from '../api/subsonic';
@@ -12,6 +13,7 @@ import LyricsPane from './LyricsPane';
 import { usePlaybackDelayPress } from '../hooks/usePlaybackDelayPress';
 import PlaybackDelayModal from './PlaybackDelayModal';
 import PlaybackScheduleBadge from './PlaybackScheduleBadge';
+import { usePlaybackScheduleRemaining } from '../utils/playbackScheduleFormat';
 
 // ── Color extraction ──────────────────────────────────────────────────────────
 // Samples a 16×16 canvas to find the most vibrant (highest-saturation,
@@ -168,6 +170,7 @@ export default function MobilePlayerView() {
   const { delayModalOpen, setDelayModalOpen, playPauseBind } = usePlaybackDelayPress(togglePlay);
   const transportAnchorRef = useRef<HTMLDivElement>(null);
   const playSlotRef = useRef<HTMLSpanElement>(null);
+  const scheduleRemaining = usePlaybackScheduleRemaining();
   const next         = usePlayerStore(s => s.next);
   const previous     = usePlayerStore(s => s.previous);
   const seek         = usePlayerStore(s => s.seek);
@@ -386,9 +389,15 @@ export default function MobilePlayerView() {
             type="button"
             {...playPauseBind}
             aria-label={isPlaying ? t('player.pause') : t('player.play')}
-            title={isPlaying ? t('player.pause') : t('player.play')}
           >
-            {isPlaying ? <Pause size={32} fill="currentColor" /> : <Play size={32} fill="currentColor" />}
+            {scheduleRemaining != null ? (
+              <span className={`player-btn-schedule-stack player-btn-schedule-stack--${scheduleRemaining.mode} player-btn-schedule-stack--mobile`}>
+                {scheduleRemaining.mode === 'pause'
+                  ? <Moon size={13} strokeWidth={2.5} />
+                  : <Sunrise size={13} strokeWidth={2.5} />}
+                <span className="player-btn-schedule-time player-btn-schedule-time--mobile">{scheduleRemaining.remaining}</span>
+              </span>
+            ) : isPlaying ? <Pause size={32} fill="currentColor" /> : <Play size={32} fill="currentColor" />}
           </button>
         </span>
         <button className="mp-ctrl-btn" onClick={() => next()} aria-label={t('player.next')}>