D3: Wire health preflight into pipeline before whisper submission

- Add health preflight gate after ensureWhisperRunning, before submitJob
- Uses getHealth() (existing) + retryWithBackoff for transient failures
- Network errors wrapped with 'whisper health check failed:' prefix
- Non-ok status fails job early with actual status in error message
- Revert compose.yaml 'name: tonemark' removal (out of scope change)
- Restore health-preflight.test.ts (228-line test covering all ACs)
- 8 test cases, 202 total tests passing, typecheck clean, build OK

src/lib/server/pipeline.ts

@@ -1,7 +1,8 @@
 import { createJob, updateJob, setJobStatus, getJob, resetJob } from './db.js';
 import { downloadYouTube, saveUploadedFile, cleanupJobTmp, getUploadPath, cleanupUploadDir } from './downloader.js';
 import { prepareAudio, cleanup as cleanupFiles } from './audio.js';
-import { submitJob, streamJob } from './whisper.js';
+import { submitJob, streamJob, getHealth } from './whisper.js';
+import { retryWithBackoff } from './retry.js';
 import { ensureWhisperRunning } from './docker.js';
 import type { AudioMode, Segment } from '$lib/types.js';
 
@@ -151,6 +152,30 @@ async function runJob(
 		// ── 3. Ensure whisper is running ──────────────────────────────────────
 		await ensureWhisperRunning();
 
+		// ── 3b. Health preflight ────────────────────────────────────────────
+		try {
+			await retryWithBackoff(
+				async () => {
+					const health = await getHealth();
+					if (health.status !== 'ok') {
+						throw new Error(`whisper health check failed: whisper status is "${health.status}"`);
+					}
+				},
+				{
+					maxAttempts: 2,
+					baseDelayMs: 1000,
+					onAttempt: (err, attempt, ms) =>
+						console.warn(`[pipeline] health check attempt ${attempt} failed, retry in ${ms}ms:`, err)
+				}
+			);
+		} catch (err) {
+			const msg = err instanceof Error ? err.message : String(err);
+			if (!msg.startsWith('whisper health check failed:')) {
+				throw new Error(`whisper health check failed: ${msg}`);
+			}
+			throw err;
+		}
+
 		// ── 4. Submit to whisper with webhook ────────────────────────────────
 		setJobStatus(jobId, 'transcribing', 10);
 		emitProgress(jobId, { type: 'status', status: 'transcribing', progress: 10 });