feat: custom formats (WxH/stickerN), JPG output option, failed-job status

- format.ts parses free formats from the key: sticker<N> -> N×N cm,
  <W>x<H> -> W×H cm. Fixes 'Unbekanntes Format: sticker5' (the seeded
  'Sticker 5 cm' recipe was unusable) and lets admins define ANY format
  without a migration. Guarded to <=300 cm.
- Output file format PNG/JPG: global default (settings.output_ext) plus
  per-recipe/per-conversion override. JPG only for non-alpha; cutouts
  stay PNG. file.ts sniffs content-type from magic bytes.
- Jobs can now be 'failed' (all items failed) -> red in the queue; add
  finished time to queue list + detail. migration 012.
- Studio: custom-measure input + Dateiformat selector; Admin: global
  Standard-Dateiformat.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XNQ8ghPfzAfsyVYd6HgFb6

src/pages/api/admin/settings.ts

@@ -25,6 +25,7 @@ export const GET: APIRoute = async () => {
     keep_sources: s.keep_sources, make_thumbnails: s.make_thumbnails, retention_days: s.retention_days,
     metadata_sidecar: s.metadata_sidecar, api_token: s.api_token,
     picdrop_metadata_sidecar: s.picdrop_metadata_sidecar, nas_metadata_sidecar: s.nas_metadata_sidecar,
+    output_ext: s.output_ext,
     // Rechte / Datenschutz / NSFW
     library_visibility: s.library_visibility, anonymous_generations: s.anonymous_generations,
     private_allowed: s.private_allowed, allow_nsfw: s.allow_nsfw,
@@ -48,7 +49,7 @@ export const PATCH: APIRoute = async ({ request }) => {
   for (const col of ['picdrop_host', 'picdrop_protocol', 'picdrop_port', 'picdrop_user', 'picdrop_base_path',
     'picdrop_default_gallery', 'default_dpi', 'default_crop_mode', 'concurrency', 'cricut_sheet_cm', 'monthly_budget', 'n8n_webhook_url',
     'keep_sources', 'make_thumbnails', 'retention_days', 'metadata_sidecar', 'api_token',
-    'picdrop_metadata_sidecar', 'nas_metadata_sidecar',
+    'picdrop_metadata_sidecar', 'nas_metadata_sidecar', 'output_ext',
     'library_visibility', 'anonymous_generations', 'private_allowed', 'allow_nsfw',
     'nas_enabled', 'nas_host', 'nas_protocol', 'nas_port', 'nas_user', 'nas_base_path']) {
     if (col in b) {

src/pages/api/items/[id]/file.ts

@@ -31,7 +31,12 @@ export const GET: APIRoute = async ({ params, url, locals }) => {
   try {
     let buf = await getObject(path);
     const download = q.get('download') === '1';
-    let contentType = path.endsWith('.webp') ? 'image/webp' : 'image/png';
+    // Inhaltstyp aus den Magic Bytes ableiten — Ergebnisse können PNG oder JPG sein.
+    const sniff = (b: Buffer): string =>
+      b.length > 3 && b[0] === 0xff && b[1] === 0xd8 && b[2] === 0xff ? 'image/jpeg'
+      : b.length > 12 && b.toString('ascii', 8, 12) === 'WEBP' ? 'image/webp'
+      : 'image/png';
+    let contentType = path.endsWith('.webp') ? 'image/webp' : sniff(buf);
     // Schnelle Vollbild-Vorschau: nicht-transparente Ergebnisse als JPEG (deutlich kleiner,
     // schneller auf Mobil) — reicht fürs „In Fotos sichern". Der PNG-Download bleibt unverändert.
     if (q.get('preview') === '1' && !download && !item?.has_alpha) {

src/pages/api/recipes.ts

@@ -16,11 +16,12 @@ export const POST: APIRoute = async ({ request, locals }) => {
   const b = await request.json();
   const row = await one(
     `INSERT INTO recipes (name, tasks, output_format, orientation, crop_mode, dpi, contour_mm,
-       model_key, delivery, picdrop_gallery, delivery_target_id, custom_instruction, mode, is_default, created_by)
-     VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9,$10,$11,$12,$13,false,$14) RETURNING *`,
+       model_key, delivery, picdrop_gallery, delivery_target_id, custom_instruction, mode, output_ext, is_default, created_by)
+     VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9,$10,$11,$12,$13,$14,false,$15) RETURNING *`,
     [b.name, JSON.stringify(b.tasks || []), b.output_format, b.orientation, b.crop_mode || 'crop',
      b.dpi || 300, b.contour_mm ?? null, b.model_key ?? null, b.delivery || 'library',
      b.picdrop_gallery ?? null, b.delivery_target_id ?? null, b.custom_instruction ?? null,
-     ['each', 'compose', 'generate'].includes(b.mode) ? b.mode : 'each', locals.user.uid]);
+     ['each', 'compose', 'generate'].includes(b.mode) ? b.mode : 'each',
+     (b.output_ext === 'jpg' || b.output_ext === 'png') ? b.output_ext : null, locals.user.uid]);
   return json({ recipe: row });
 };

src/pages/api/recipes/[id].ts

@@ -6,7 +6,7 @@ const json = (b: unknown, s = 200) =>
   new Response(JSON.stringify(b), { status: s, headers: { 'Content-Type': 'application/json' } });
 
 const COLS = ['name', 'tasks', 'output_format', 'orientation', 'crop_mode', 'dpi', 'contour_mm',
-  'model_key', 'delivery', 'picdrop_gallery', 'delivery_target_id', 'custom_instruction', 'mode'];
+  'model_key', 'delivery', 'picdrop_gallery', 'delivery_target_id', 'custom_instruction', 'mode', 'output_ext'];
 
 export const PATCH: APIRoute = async ({ params, request, locals }) => {
   if (!locals.user) return new Response('Unauthorized', { status: 401 });