feat: add auto-increment id, size/duration tracking, and soft cleanup to conversion_jobs

Rename the old CHAR(36) id to uuid (still used for public URLs and file
naming) and add a real auto-increment id as the primary key. Track
input/output file size and conversion duration per job. Cleanup no
longer deletes rows; it marks cleaned_at and skips already-cleaned
expired jobs on later runs.

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

src/app.js

@@ -10,7 +10,7 @@ import { registerImageToPdfConverter } from './converters/imageToPdf.js';
 import { registerDocumentConverters } from './converters/document.js';
 import { resolveInputFormat } from './mime.js';
 import { deleteIfExists } from './storage.js';
-import { createJob, getJobById } from './jobs/jobRepository.js';
+import { createJob, getJobByUuid } from './jobs/jobRepository.js';
 import { outputPath } from './storage.js';
 
 let convertersRegistered = false;
@@ -77,7 +77,7 @@ export function createApp(config, pool) {
     for (let i = 0; i < req.files.length; i += 1) {
       const file = req.files[i];
       const targetFormat = targetFormats[i];
-      const id = path.basename(file.filename, path.extname(file.filename));
+      const uuid = path.basename(file.filename, path.extname(file.filename));
       const sourceFormat = path.extname(file.filename).slice(1).toLowerCase();
 
       const { mime, valid } = await resolveInputFormat(file.path, sourceFormat);
@@ -99,30 +99,31 @@ export function createApp(config, pool) {
 
       const expiresAt = new Date(Date.now() + config.retentionHours * 3600 * 1000);
       await createJob(pool, {
-        id,
+        uuid,
         family: registryEntry.family,
         sourceFormat,
         targetFormat,
         originalFilename: file.originalname,
         inputPath: file.filename,
         inputMimeType: mime,
+        inputSizeBytes: file.size,
         expiresAt,
       });
 
-      results.push({ file: file.originalname, id, status: 'pending' });
+      results.push({ file: file.originalname, id: uuid, status: 'pending' });
     }
 
     res.status(201).json({ jobs: results });
   });
 
   app.get('/api/jobs/:id', async (req, res) => {
-    const job = await getJobById(pool, req.params.id);
+    const job = await getJobByUuid(pool, req.params.id);
     if (!job) {
       return res.status(404).json({ error: 'Job not found' });
     }
 
     res.json({
-      id: job.id,
+      id: job.uuid,
       status: job.status,
       originalFilename: job.originalFilename,
       sourceFormat: job.sourceFormat,
@@ -138,7 +139,7 @@ export function createApp(config, pool) {
   }
 
   app.get('/api/jobs/:id/download', async (req, res) => {
-    const job = await getJobById(pool, req.params.id);
+    const job = await getJobByUuid(pool, req.params.id);
     if (!job) {
       return res.status(404).json({ error: 'Job not found' });
     }
@@ -146,7 +147,7 @@ export function createApp(config, pool) {
       return res.status(409).json({ error: `Job is not ready yet (status: ${job.status})` });
     }
 
-    const filePath = outputPath(config, job.id, job.targetFormat);
+    const filePath = outputPath(config, job.uuid, job.targetFormat);
     const downloadFilename = `${path.parse(job.originalFilename).name}.${job.targetFormat}`;
     res.set('Content-Type', job.outputMimeType);
     res.set('Content-Disposition', contentDispositionHeader(downloadFilename));