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/test3-ultrawide.js

@@ -0,0 +1,76 @@
+'use strict';
+
+/**
+ * test3-ultrawide.js
+ * Validates: transcode2PassX265 scale filter on 3840x1600 input.
+ * Expected output: 1920x800 (no letterbox, even dimensions).
+ */
+
+const path   = require('path');
+const fs     = require('fs');
+const { execSync } = require('child_process');
+const { buildMockArgs, cleanupWorkDir, assert, assertEqual } = require('../mock-tdarr-runtime');
+const { plugin: analyzerPlugin }   = require('../../LocalFlowPlugins/utility/mediaAnalyzerGOP/1.0.0/index');
+const { plugin: audioPlugin }      = require('../../LocalFlowPlugins/audio/audioSelectorClamping/1.0.0/index');
+const { plugin: transcodePlugin }  = require('../../LocalFlowPlugins/video/transcode2PassX265/1.0.0/index');
+
+const FILE   = path.resolve('tests/samples/test3_ultrawide.mkv');
+const FFMPEG  = process.env.FFMPEG_PATH  || 'ffmpeg';
+const FFPROBE = process.env.FFPROBE_PATH || 'ffprobe';
+
+async function run() {
+  console.log('\n=== TEST 3: Ultrawide 3840x1600 Scale Filter ===\n');
+
+  // Analyzer
+  const args1 = buildMockArgs({
+    filePath: FILE,
+    inputs: { moviePathPatterns: '/Radarr', animeSeries: '', filmBitrate: '3000',
+              seriesBitrate: '3000', animeBitrateHd: '2000', animeBitrateSd: '1000' },
+  });
+  const out1 = await analyzerPlugin(args1);
+  const vars = out1.variables;
+  assertEqual(vars.videoHeight, '1600', 'Source videoHeight = 1600');
+
+  // Audio selector
+  const args2 = buildMockArgs({
+    filePath: FILE, variables: vars,
+    inputs: { filmMultiChannelBitrate: '640', seriesMultiChannelThreshold: '384', stereoBitrateMax: '128' },
+  });
+  const out2 = await audioPlugin(args2);
+
+  // Transcode (Pass 1 + Pass 2)
+  console.log('Running transcode2PassX265 (this may take a minute)...');
+  const args3 = buildMockArgs({
+    filePath: FILE,
+    variables: out2.variables,
+    inputs: { x265Preset: 'ultrafast', outputContainer: 'mkv' },
+    ffmpegPath: FFMPEG,
+  });
+
+  const out3 = await transcodePlugin(args3);
+  const outFile = out3.outputFileObj._id;
+
+  assert(fs.existsSync(outFile), `Output file exists: ${outFile}`);
+
+  // Verify dimensions with ffprobe
+  const probeOut = execSync(
+    `${FFPROBE} -v quiet -print_format json -show_streams -select_streams v:0 "${outFile}"`,
+    { encoding: 'utf8' },
+  );
+  const { streams } = JSON.parse(probeOut);
+  const w = streams[0].width;
+  const h = streams[0].height;
+
+  console.log(`  Output dimensions: ${w}x${h}`);
+  assert(w === 1920, `Width = 1920 (got ${w})`);
+  assert(h === 800,  `Height = 800 (got ${h})`);
+  assert(w % 2 === 0, 'Width is even');
+  assert(h % 2 === 0, 'Height is even');
+
+  cleanupWorkDir(args1);
+  cleanupWorkDir(args2);
+  cleanupWorkDir(args3);
+  console.log('\n=== TEST 3 PASSED ===\n');
+}
+
+module.exports = run;