fix(analysis): native library backfill coordinator for advanced strategy (#881)

* feat(analysis): native library backfill coordinator for advanced strategy

Move advanced analytics scheduling from the webview loop into a Rust
background worker (configure + spawn_blocking batch/enqueue), matching
cover backfill. Scan hash+BPM gap tracks instead of the full library;
suppress low-priority analysis UI events; limit loudness refresh IPC to
the playback window.

* fix(analysis): flat backfill configure IPC and restore probe track-perf

Use flattened Tauri args like cover backfill so release/prod invoke works;
keep emitting analysis:track-perf for library low-priority work so Performance
Probe tpm/last-track stats update while waveform/enrichment UI events stay suppressed.

* chore(analysis): fix clippy and drop duplicate TS backfill policy

Allow too_many_arguments on library_analysis_backfill_configure for CI;
remove unused frontend batch API and TS watermark helpers now owned in Rust;
clarify analysis_emits_ui_events comment for low-priority track-perf.

* docs: CHANGELOG and credits for PR #881 native analysis backfill

src/utils/library/libraryAnalysisBackfillPolicy.test.ts

@@ -1,48 +0,0 @@
-import { describe, it, expect } from 'vitest';
-import {
-  computeLibraryBackfillTargetDepth,
-  libraryBackfillNeedsTopUp,
-  libraryBackfillPipelineBacklog,
-  libraryBackfillTopUpLimit,
-} from './libraryAnalysisBackfillPolicy';
-
-describe('libraryAnalysisBackfillPolicy', () => {
-  it('targets workers × 3 with floor and cap', () => {
-    expect(computeLibraryBackfillTargetDepth(1)).toBe(8);
-    expect(computeLibraryBackfillTargetDepth(4)).toBe(12);
-    expect(computeLibraryBackfillTargetDepth(8)).toBe(24);
-    expect(computeLibraryBackfillTargetDepth(100)).toBe(240);
-  });
-
-  const zeroCpu = { cpuQueued: 0, cpuDecodeActive: 0 };
-
-  it('measures backlog as HTTP plus CPU seed pipeline load', () => {
-    expect(
-      libraryBackfillPipelineBacklog({
-        httpQueued: 5,
-        httpDownloadActive: 3,
-        ...zeroCpu,
-      }),
-    ).toBe(8);
-    expect(
-      libraryBackfillPipelineBacklog({
-        httpQueued: 0,
-        httpDownloadActive: 0,
-        cpuQueued: 4,
-        cpuDecodeActive: 2,
-      }),
-    ).toBe(6);
-  });
-
-  it('requests top-up while backlog stays below target', () => {
-    const stats = { httpQueued: 2, httpDownloadActive: 1, ...zeroCpu };
-    expect(libraryBackfillNeedsTopUp(stats, 8)).toBe(true);
-    expect(libraryBackfillTopUpLimit(stats, 8)).toBe(20);
-  });
-
-  it('stops top-up when backlog meets target', () => {
-    const stats = { httpQueued: 20, httpDownloadActive: 4, ...zeroCpu };
-    expect(libraryBackfillNeedsTopUp(stats, 8)).toBe(false);
-    expect(libraryBackfillTopUpLimit(stats, 8)).toBe(0);
-  });
-});

src/utils/library/libraryAnalysisBackfillPolicy.ts

@@ -1,41 +0,0 @@
-import type { AnalysisPipelineQueueStatsDto } from '../../api/analysis';
-import { LIBRARY_ANALYSIS_BACKFILL_BATCH_SIZE } from '../../api/analysis';
-
-/** Target backlog ≈ workers × multiplier (min floor, max cap). */
-export const LIBRARY_BACKLOG_DEPTH_MULTIPLIER = 3;
-export const LIBRARY_BACKLOG_MIN = 8;
-export const LIBRARY_BACKLOG_MAX = 240;
-
-export function computeLibraryBackfillTargetDepth(workers: number): number {
-  const w = Math.max(1, Math.round(workers));
-  return Math.min(
-    LIBRARY_BACKLOG_MAX,
-    Math.max(LIBRARY_BACKLOG_MIN, w * LIBRARY_BACKLOG_DEPTH_MULTIPLIER),
-  );
-}
-
-type PipelineBacklogStats = Pick<
-  AnalysisPipelineQueueStatsDto,
-  'httpQueued' | 'httpDownloadActive' | 'cpuQueued' | 'cpuDecodeActive'
->;
-
-/** HTTP + in-flight CPU seed jobs (decode backpressure must not look like an empty pipeline). */
-export function libraryBackfillPipelineBacklog(stats: PipelineBacklogStats): number {
-  return (
-    stats.httpQueued
-    + stats.httpDownloadActive
-    + stats.cpuQueued
-    + stats.cpuDecodeActive
-  );
-}
-
-export function libraryBackfillNeedsTopUp(stats: PipelineBacklogStats, workers: number): boolean {
-  return libraryBackfillPipelineBacklog(stats) < computeLibraryBackfillTargetDepth(workers);
-}
-
-export function libraryBackfillTopUpLimit(stats: PipelineBacklogStats, workers: number): number {
-  const target = computeLibraryBackfillTargetDepth(workers);
-  const deficit = target - libraryBackfillPipelineBacklog(stats);
-  if (deficit <= 0) return 0;
-  return Math.min(LIBRARY_ANALYSIS_BACKFILL_BATCH_SIZE, deficit);
-}