feat: Tdarr Local Flow Plugin Suite v1.0

7 atomic plugins for automated x265 transcoding pipeline:
- utility/mediaAnalyzerGOP    : GOP calc, FPS detection, film/series/anime routing
- utility/setAnimationFlag    : manual animation flag override
- utility/extractChaptersXml  : mkvextract chapters to XML
- audio/audioSelectorClamping : codec scoring, clamped Opus bitrates, 2 outputs
- audio/backupSourceAudio     : lossless DTS/TrueHD ITA backup (-c:a copy)
- subtitles/extractSubtitlesAndOcr : SRT extract + SubtitleEdit OCR for PGS
- video/transcode2PassX265    : 2-pass x265, Lanczos 1080p bound, Opus mux

Test suite: 34 unit tests + 3 integration tests (FFmpeg real files)
FlowHelpers mock for local testing included
Docs: integration-guide.md with canvas wiring and deploy instructions

tests/test-cases/test4-subtitles.js

@@ -0,0 +1,50 @@
+'use strict';
+
+/**
+ * test4-subtitles.js
+ * Validates: extractSubtitlesAndOcr produces correctly named SRT files.
+ * Source: MKV with 2 ITA SRT streams (forced + SDH).
+ * Expected: .ita.forced.srt and .ita.hearing_impaired.srt in source dir.
+ */
+
+const path = require('path');
+const fs   = require('fs');
+const { buildMockArgs, cleanupWorkDir, assert } = require('../mock-tdarr-runtime');
+const { plugin: subPlugin } = require('../../LocalFlowPlugins/subtitles/extractSubtitlesAndOcr/1.0.0/index');
+
+const FILE      = path.resolve('tests/samples/test4_subtitles.mkv');
+const SOURCE_DIR = path.dirname(FILE);
+const BASE_NAME  = path.basename(FILE, '.mkv');
+
+async function run() {
+  console.log('\n=== TEST 4: Subtitle Extraction (forced + SDH) ===\n');
+
+  const args = buildMockArgs({
+    filePath: FILE,
+    inputs: { subtitleEditPath: 'SubtitleEdit', languages: 'ita,eng' },
+  });
+
+  await subPlugin(args);
+
+  // Check that forced SRT was created
+  const forcedSrt = path.join(SOURCE_DIR, `${BASE_NAME}.ita.forced.srt`);
+  const sdhSrt    = path.join(SOURCE_DIR, `${BASE_NAME}.ita.sdh.srt`);
+
+  console.log('  Checking for:', path.basename(forcedSrt));
+  assert(fs.existsSync(forcedSrt), `Forced SRT exists: ${path.basename(forcedSrt)}`);
+
+  console.log('  Checking for:', path.basename(sdhSrt));
+  // Note: disposition hearing_impaired maps to 'sdh' suffix
+  // If not found, check for .ita.default.srt variant (FFmpeg disposition naming may vary)
+  const sdhExists   = fs.existsSync(sdhSrt);
+  const altSdhExists = fs.existsSync(path.join(SOURCE_DIR, `${BASE_NAME}.ita.default.srt`));
+  assert(sdhExists || altSdhExists, `SDH/hearing-impaired SRT exists`);
+
+  // Cleanup generated subtitle files
+  [forcedSrt, sdhSrt].forEach((f) => { try { fs.unlinkSync(f); } catch (_) {} });
+
+  cleanupWorkDir(args);
+  console.log('\n=== TEST 4 PASSED ===\n');
+}
+
+module.exports = run;