Wire the app, worker, and cleanup entry points onto Prisma Client

Task 4 rewrote src/db.js and src/jobs/jobRepository.js to use Prisma
instead of the hand-rolled mariadb pool. This updates every remaining
call site (app.js, server.js, worker.js, cleanup.js) and the 5 test
files that still referenced getPool/closePool/pool.query, so the app
and full test suite compile and run against Prisma Client.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/worker.js

@@ -1,7 +1,7 @@
 import { pathToFileURL } from 'node:url';
 import fs from 'node:fs/promises';
 import { loadConfig } from './config.js';
-import { getPool } from './db.js';
+import { getPrismaClient } from './db.js';
 import { ensureStorageDirs, uploadPath, outputPath, deleteIfExists } from './storage.js';
 import { outputMimeType } from './mime.js';
 import { resolve as resolveConverter } from './converters/registry.js';
@@ -20,8 +20,8 @@ function withTimeout(promise, ms) {
   return Promise.race([promise, timeout]).finally(() => clearTimeout(timeoutId));
 }
 
-async function processJob(pool, config, job) {
-  await markProcessing(pool, job.id);
+async function processJob(prisma, config, job) {
+  await markProcessing(prisma, job.id);
 
   const inputFilePath = uploadPath(config, job.uuid, job.sourceFormat);
   const outputFilePath = outputPath(config, job.uuid, job.targetFormat);
@@ -37,7 +37,7 @@ async function processJob(pool, config, job) {
     const conversionDurationSeconds = (Date.now() - startedAt) / 1000;
     const { size: outputSizeBytes } = await fs.stat(outputFilePath);
 
-    await markDone(pool, job.id, {
+    await markDone(prisma, job.id, {
       outputPath: `${job.uuid}.${job.targetFormat}`,
       outputMimeType: outputMimeType(job.targetFormat),
       outputSizeBytes,
@@ -45,22 +45,22 @@ async function processJob(pool, config, job) {
     });
   } catch (error) {
     await deleteIfExists(outputFilePath);
-    await markFailed(pool, job.id, {
+    await markFailed(prisma, job.id, {
       errorMessage: 'Conversion failed, please try again.',
       errorLog: error.stack ?? String(error),
     });
   }
 }
 
-export async function processPendingJobs(pool, config) {
-  const jobs = await findPendingJobs(pool, config.workerConcurrency);
-  await Promise.all(jobs.map((job) => processJob(pool, config, job)));
+export async function processPendingJobs(prisma, config) {
+  const jobs = await findPendingJobs(prisma, config.workerConcurrency);
+  await Promise.all(jobs.map((job) => processJob(prisma, config, job)));
   return jobs.length;
 }
 
-export function startWorker(pool, config) {
+export function startWorker(prisma, config) {
   const interval = setInterval(() => {
-    processPendingJobs(pool, config).catch((error) => {
+    processPendingJobs(prisma, config).catch((error) => {
       console.error('Error while processing pending jobs:', error);
     });
   }, config.workerPollIntervalMs);
@@ -70,14 +70,14 @@ export function startWorker(pool, config) {
 async function main() {
   const config = loadConfig();
   await ensureStorageDirs(config);
-  const pool = getPool(config);
+  const prisma = getPrismaClient(config);
 
   registerImageConverters();
   registerImageToPdfConverter();
   registerDocumentConverters();
 
-  startWorker(pool, config);
+  startWorker(prisma, config);
   console.log(`Worker started, polling every ${config.workerPollIntervalMs}ms`);
 }
 
-main();
+main();