feat: model selection+visibility, better filenames, picdrop direct upload + configurable gallery

- studio: quality/model selector (friendly names from active models); library shows model used
- seed 2 models (Schnell/Beste Qualitaet); GET /api/models for studio+library
- filename: YYYY-MM-DD_motif_format.png (was redundant slug, no date)
- picdrop: direct upload to final name (fix .tmp- leftover from failed rename on picdrop); cleanupTmp helper
- configurable default gallery (migration 003, settings + admin field); base_path=SFTP root, gallery=subfolder

src/lib/pipeline.ts

@@ -82,13 +82,31 @@ export async function heicToPng(buffer: Buffer): Promise<Buffer> {
   return Buffer.from(out);
 }
 
-/** Deutscher Datei-Slug: klein, mit Bindestrichen, Format angehängt. */
-export function slugFilename(base: string, formatLabel: string, ext = 'png'): string {
-  const slug = (base || 'bild')
+/** Klein, mit Bindestrichen, ohne Umlaut-Probleme. */
+export function slugify(s: string): string {
+  return (s || '')
     .toLowerCase()
     .replace(/[äöüß]/g, (c) => ({ ä: 'ae', ö: 'oe', ü: 'ue', ß: 'ss' }[c] || c))
     .normalize('NFKD').replace(/[̀-ͯ]/g, '')
-    .replace(/[^a-z0-9]+/g, '-').replace(/^-+|-+$/g, '').slice(0, 60) || 'bild';
-  const fmt = formatLabel.toLowerCase().replace(/[^a-z0-9]+/g, '');
-  return `${slug}${fmt ? '-' + fmt : ''}.${ext}`;
+    .replace(/[^a-z0-9]+/g, '-').replace(/^-+|-+$/g, '').slice(0, 48);
+}
+
+const GENERIC = new Set(['', 'foto', 'photo', 'bild', 'image', 'img', 'telegram', 'unbenannt', 'klarbild', 'screenshot', 'pxl', 'whatsapp']);
+
+/** Logischer Dateiname: JJJJ-MM-TT_<motiv>_<format>.<ext>
+ *  z. B. 2026-07-23_lea_the-frame.png */
+export function buildResultFilename(originalName: string | null, formatToken: string, ext = 'png'): string {
+  const raw = slugify((originalName || '').replace(/\.[^.]+$/, ''));
+  const motif = GENERIC.has(raw) ? 'klarbild' : raw;
+  const date = new Date().toISOString().slice(0, 10);
+  const fmt = slugify(formatToken) || 'original';
+  return `${date}_${motif}_${fmt}.${ext}`;
+}
+
+/** Formatschlüssel für den Dateinamen (aus dem output_format). */
+export function formatToken(outputFormat: string | undefined): string {
+  if (!outputFormat || outputFormat === 'keep') return 'original';
+  if (outputFormat === 'theframe') return 'the-frame';
+  if (outputFormat === 'hochformat') return 'hochformat';
+  return outputFormat.toLowerCase(); // 30x40, a4, sticker, …
 }