feat(TRUEREF-0020): add job status page with pause/resume/cancel controls

- Extend indexing_jobs schema to support 'paused' and 'cancelled' status
- Add JobQueue methods: pauseJob(), resumeJob(), cancelJob()
- Create POST /api/v1/jobs/[id]/{pause,resume,cancel} endpoints
- Implement /admin/jobs page with auto-refresh (3s polling)
- Add JobStatusBadge component with color-coded status display
- Action buttons appear contextually based on job status
- Optimistic UI updates with error handling
- All 477 existing tests pass, no regressions

src/routes/api/v1/jobs/[id]/cancel/+server.ts

@@ -0,0 +1,45 @@
+/**
+ * POST /api/v1/jobs/:id/cancel — cancel a job.
+ */
+
+import { json } from '@sveltejs/kit';
+import type { RequestHandler } from './$types';
+import { getClient } from '$lib/server/db/client.js';
+import { IndexingJobMapper } from '$lib/server/mappers/indexing-job.mapper.js';
+import { JobQueue } from '$lib/server/pipeline/job-queue.js';
+import { handleServiceError, NotFoundError, InvalidInputError } from '$lib/server/utils/validation.js';
+
+export const POST: RequestHandler = ({ params }) => {
+	try {
+		const db = getClient();
+		const queue = new JobQueue(db);
+
+		const job = queue.getJob(params.id);
+		if (!job) throw new NotFoundError(`Job ${params.id} not found`);
+
+		const success = queue.cancelJob(params.id);
+		if (!success) {
+			throw new InvalidInputError(
+				`Cannot cancel job ${params.id} - job is already done or failed`
+			);
+		}
+
+		// Fetch updated job
+		const updated = queue.getJob(params.id)!;
+
+		return json({ success: true, job: IndexingJobMapper.toDto(updated) });
+	} catch (err) {
+		return handleServiceError(err);
+	}
+};
+
+export const OPTIONS: RequestHandler = () => {
+	return new Response(null, {
+		status: 204,
+		headers: {
+			'Access-Control-Allow-Origin': '*',
+			'Access-Control-Allow-Methods': 'POST, OPTIONS',
+			'Access-Control-Allow-Headers': 'Content-Type, Authorization'
+		}
+	});
+};

src/routes/api/v1/jobs/[id]/pause/+server.ts

@@ -0,0 +1,45 @@
+/**
+ * POST /api/v1/jobs/:id/pause — pause a running or queued job.
+ */
+
+import { json } from '@sveltejs/kit';
+import type { RequestHandler } from './$types';
+import { getClient } from '$lib/server/db/client.js';
+import { IndexingJobMapper } from '$lib/server/mappers/indexing-job.mapper.js';
+import { JobQueue } from '$lib/server/pipeline/job-queue.js';
+import { handleServiceError, NotFoundError, InvalidInputError } from '$lib/server/utils/validation.js';
+
+export const POST: RequestHandler = ({ params }) => {
+	try {
+		const db = getClient();
+		const queue = new JobQueue(db);
+
+		const job = queue.getJob(params.id);
+		if (!job) throw new NotFoundError(`Job ${params.id} not found`);
+
+		const success = queue.pauseJob(params.id);
+		if (!success) {
+			throw new InvalidInputError(
+				`Cannot pause job ${params.id} - only queued or running jobs can be paused`
+			);
+		}
+
+		// Fetch updated job
+		const updated = queue.getJob(params.id)!;
+
+		return json({ success: true, job: IndexingJobMapper.toDto(updated) });
+	} catch (err) {
+		return handleServiceError(err);
+	}
+};
+
+export const OPTIONS: RequestHandler = () => {
+	return new Response(null, {
+		status: 204,
+		headers: {
+			'Access-Control-Allow-Origin': '*',
+			'Access-Control-Allow-Methods': 'POST, OPTIONS',
+			'Access-Control-Allow-Headers': 'Content-Type, Authorization'
+		}
+	});
+};

src/routes/api/v1/jobs/[id]/resume/+server.ts

@@ -0,0 +1,43 @@
+/**
+ * POST /api/v1/jobs/:id/resume — resume a paused job.
+ */
+
+import { json } from '@sveltejs/kit';
+import type { RequestHandler } from './$types';
+import { getClient } from '$lib/server/db/client.js';
+import { IndexingJobMapper } from '$lib/server/mappers/indexing-job.mapper.js';
+import { JobQueue } from '$lib/server/pipeline/job-queue.js';
+import { handleServiceError, NotFoundError, InvalidInputError } from '$lib/server/utils/validation.js';
+
+export const POST: RequestHandler = ({ params }) => {
+	try {
+		const db = getClient();
+		const queue = new JobQueue(db);
+
+		const job = queue.getJob(params.id);
+		if (!job) throw new NotFoundError(`Job ${params.id} not found`);
+
+		const success = queue.resumeJob(params.id);
+		if (!success) {
+			throw new InvalidInputError(`Cannot resume job ${params.id} - only paused jobs can be resumed`);
+		}
+
+		// Fetch updated job
+		const updated = queue.getJob(params.id)!;
+
+		return json({ success: true, job: IndexingJobMapper.toDto(updated) });
+	} catch (err) {
+		return handleServiceError(err);
+	}
+};
+
+export const OPTIONS: RequestHandler = () => {
+	return new Response(null, {
+		status: 204,
+		headers: {
+			'Access-Control-Allow-Origin': '*',
+			'Access-Control-Allow-Methods': 'POST, OPTIONS',
+			'Access-Control-Allow-Headers': 'Content-Type, Authorization'
+		}
+	});
+};