refactor(format): consolidate duration formatters into format/formatDuration (Phase L, part 2) (#690)

The mm:ss track-time formatter was hand-rolled in 11 places and the
h:mm:ss total-duration formatter in 4 — extract two tested functions:

- formatTrackTime(seconds, fallback='0:00')  — m:ss, used for track /
  playback times. fallback param covers the '–' placeholder rows.
- formatLongDuration(seconds)                — h:mm:ss when >=1h, else
  m:ss, used for album / queue totals.

Behaviour preserved per call site: the unified guard
(!seconds || !isFinite || <0 -> fallback) produces identical output to
every prior variant for all real inputs; SongRow keeps its '–' via the
fallback arg. Removes the formatter exports from 6 componentHelpers
files (playerBarHelpers / fullscreenPlayerHelpers deleted — they only
exported the formatter) and 7 inline component copies.

+ formatDuration.test.ts

src/components/playerBar/PlaybackClock.tsx

@@ -1,6 +1,6 @@
 import { memo, useEffect, useRef } from 'react';
 import { getPlaybackProgressSnapshot, subscribePlaybackProgress } from '../../store/playbackProgress';
-import { formatTime } from '../../utils/componentHelpers/playerBarHelpers';
+import { formatTrackTime } from '../../utils/format/formatDuration';
 
 /** Renders the playback clock without ever causing PlayerBar to re-render.
  *  Updates the DOM directly via an imperative store subscription. */
@@ -8,10 +8,10 @@ export const PlaybackTime = memo(function PlaybackTime({ className }: { classNam
   const spanRef = useRef<HTMLSpanElement>(null);
   useEffect(() => {
     if (spanRef.current) {
-      spanRef.current.textContent = formatTime(getPlaybackProgressSnapshot().currentTime);
+      spanRef.current.textContent = formatTrackTime(getPlaybackProgressSnapshot().currentTime);
     }
     return subscribePlaybackProgress(state => {
-      if (spanRef.current) spanRef.current.textContent = formatTime(state.currentTime);
+      if (spanRef.current) spanRef.current.textContent = formatTrackTime(state.currentTime);
     });
   }, []);
   return <span className={className} ref={spanRef} />;
@@ -25,7 +25,7 @@ export const RemainingTime = memo(function RemainingTime({ duration, className }
     const updateRemaining = () => {
       if (spanRef.current) {
         const remaining = Math.max(0, duration - getPlaybackProgressSnapshot().currentTime);
-        spanRef.current.textContent = `-${formatTime(remaining)}`;
+        spanRef.current.textContent = `-${formatTrackTime(remaining)}`;
       }
     };
     updateRemaining();

src/components/playerBar/PlayerSeekbarSection.tsx

@@ -2,7 +2,7 @@ import { ArrowLeftRight } from 'lucide-react';
 import type { TFunction } from 'i18next';
 import type { RadioMetadata } from '../../hooks/useRadioMetadata';
 import { useThemeStore } from '../../store/themeStore';
-import { formatTime } from '../../utils/componentHelpers/playerBarHelpers';
+import { formatTrackTime } from '../../utils/format/formatDuration';
 import WaveformSeek from '../WaveformSeek';
 import { PlaybackTime, RemainingTime } from './PlaybackClock';
 
@@ -27,7 +27,7 @@ export function PlayerSeekbarSection({
         <>
           {radioMeta.source === 'azuracast' && radioMeta.elapsed != null && radioMeta.duration != null && radioMeta.duration > 0 ? (
             <>
-              <span className="player-time">{formatTime(radioMeta.elapsed)}</span>
+              <span className="player-time">{formatTrackTime(radioMeta.elapsed)}</span>
               <div className="player-waveform-wrap">
                 <div className="radio-progress-bar">
                   <div
@@ -36,7 +36,7 @@ export function PlayerSeekbarSection({
                   />
                 </div>
               </div>
-              <span className="player-time">{formatTime(radioMeta.duration)}</span>
+              <span className="player-time">{formatTrackTime(radioMeta.duration)}</span>
             </>
           ) : (
             <>
@@ -65,7 +65,7 @@ export function PlayerSeekbarSection({
             }}
             data-tooltip={localShowRemaining ? t('player.showDuration') : t('player.showRemainingTime')}
           >
-            {localShowRemaining ? <RemainingTime duration={duration} /> : formatTime(duration)}
+            {localShowRemaining ? <RemainingTime duration={duration} /> : formatTrackTime(duration)}
             <ArrowLeftRight size={10} style={{ marginLeft: 4, opacity: 0.6 }} />
           </span>
         </>