fix(MULTIVERSION-0001): fix version indexing pipeline state and UI reactivity

- Add updateVersion() helper to IndexingPipeline that writes to repository_versions
- Set version state to indexing/indexed/error at the appropriate pipeline stages
- Add computeVersionStats() to count snippets for a specific version
- Replace Map<string,string> with Record<string,string|undefined> for activeVersionJobs to fix Svelte 5 reactivity edge cases
- Remove premature loadVersions() call from handleIndexVersion (oncomplete fires it instead)
- Add refreshRepo() to version oncomplete callback so stat badges update after indexing
- Disable Index button when activeVersionJobs has an entry for that tag (not just version.state)
- Add three pipeline test cases covering versionId indexing, error, and no-touch paths

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/lib/server/pipeline/indexing.pipeline.test.ts

@@ -75,6 +75,28 @@ function insertRepo(db: Database.Database, overrides: Partial<Record<string, unk
 	);
 }
 
+function insertVersion(
+	db: Database.Database,
+	overrides: Partial<Record<string, unknown>> = {}
+): string {
+	const id = crypto.randomUUID();
+	db.prepare(
+		`INSERT INTO repository_versions
+       (id, repository_id, tag, title, state, total_snippets, indexed_at, created_at)
+     VALUES (?, ?, ?, ?, ?, ?, ?, ?)`
+	).run(
+		overrides.id ?? id,
+		overrides.repository_id ?? '/test/repo',
+		overrides.tag ?? 'v1.0.0',
+		overrides.title ?? null,
+		overrides.state ?? 'pending',
+		overrides.total_snippets ?? 0,
+		overrides.indexed_at ?? null,
+		overrides.created_at ?? now
+	);
+	return (overrides.id as string) ?? id;
+}
+
 function insertJob(
 	db: Database.Database,
 	overrides: Partial<Record<string, unknown>> = {}
@@ -272,8 +294,12 @@ describe('IndexingPipeline', () => {
 		);
 	}
 
-	function makeJob(repositoryId = '/test/repo') {
-		const jobId = insertJob(db, { repository_id: repositoryId, status: 'queued' });
+	function makeJob(repositoryId = '/test/repo', versionId?: string) {
+		const jobId = insertJob(db, {
+			repository_id: repositoryId,
+			version_id: versionId ?? null,
+			status: 'queued'
+		});
 		return db.prepare(`SELECT * FROM indexing_jobs WHERE id = ?`).get(jobId) as {
 			id: string;
 			repositoryId?: string;
@@ -644,4 +670,63 @@ describe('IndexingPipeline', () => {
 		expect(finalJob.status).toBe('done');
 		expect(finalJob.progress).toBe(100);
 	});
+
+	it('updates repository_versions state to indexing then indexed when job has versionId', async () => {
+		const versionId = insertVersion(db, { tag: 'v1.0.0', state: 'pending' });
+		const files = [
+			{
+				path: 'README.md',
+				content: '# Hello\n\nThis is documentation.',
+				sha: 'sha-readme',
+				language: 'markdown'
+			}
+		];
+		const pipeline = makePipeline({ files, totalFiles: 1 });
+		const job = makeJob('/test/repo', versionId);
+
+		await pipeline.run(job as never);
+
+		const version = db
+			.prepare(`SELECT state, total_snippets, indexed_at FROM repository_versions WHERE id = ?`)
+			.get(versionId) as { state: string; total_snippets: number; indexed_at: number | null };
+
+		expect(version.state).toBe('indexed');
+		expect(version.total_snippets).toBeGreaterThan(0);
+		expect(version.indexed_at).not.toBeNull();
+	});
+
+	it('updates repository_versions state to error when pipeline throws and job has versionId', async () => {
+		const versionId = insertVersion(db, { tag: 'v1.0.0', state: 'pending' });
+		const errorCrawl = vi.fn().mockRejectedValue(new Error('crawl failed'));
+		const pipeline = new IndexingPipeline(
+			db,
+			errorCrawl as never,
+			{ crawl: errorCrawl } as never,
+			null
+		);
+		const job = makeJob('/test/repo', versionId);
+
+		await expect(pipeline.run(job as never)).rejects.toThrow('crawl failed');
+
+		const version = db
+			.prepare(`SELECT state FROM repository_versions WHERE id = ?`)
+			.get(versionId) as { state: string };
+
+		expect(version.state).toBe('error');
+	});
+
+	it('does not touch repository_versions when job has no versionId', async () => {
+		const versionId = insertVersion(db, { tag: 'v1.0.0', state: 'pending' });
+		const pipeline = makePipeline({ files: [], totalFiles: 0 });
+		const job = makeJob('/test/repo'); // no versionId
+
+		await pipeline.run(job as never);
+
+		const version = db
+			.prepare(`SELECT state FROM repository_versions WHERE id = ?`)
+			.get(versionId) as { state: string };
+
+		// State should remain 'pending' — pipeline with no versionId must not touch it
+		expect(version.state).toBe('pending');
+	});
 });