feat(api): expose outputSizeBytes on job status

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

src/app.js

@@ -83,6 +83,10 @@ export function createApp(config, prisma) {
     res.json({ targets: listTargetFormats(source) });
   });
 
+  app.get('/api/config', (req, res) => {
+    res.json({ maxFileSizeMb: config.maxFileSizeMb, retentionHours: config.retentionHours });
+  });
+
   app.post('/api/jobs', jobsRateLimiter, upload.array('files', 10), async (req, res) => {
     if (!req.files || req.files.length === 0) {
       return res.status(400).json({ error: 'No files uploaded' });
@@ -206,6 +210,7 @@ export function createApp(config, prisma) {
       originalFilename: job.originalFilename,
       sourceFormat: job.sourceFormat,
       targetFormat: job.targetFormat,
+      outputSizeBytes: job.outputSizeBytes,
       errorMessage: job.errorMessage,
     });
   });