feat: multiple delivery targets (FTP/SFTP), per-preset wiring; The Frame -> TheFrame-Backgrounds gallery

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

migrations/007_delivery_targets.sql

@@ -0,0 +1,21 @@
+-- Mehrere Auslieferungsziele (FTP/SFTP-Quellen), z. B. eine zweite Picdrop-Galerie
+-- oder ein anderer FTP-Server. Rezepte/Presets können ein Ziel fest verdrahten.
+CREATE TABLE IF NOT EXISTS delivery_targets (
+  id           uuid PRIMARY KEY DEFAULT gen_random_uuid(),
+  name         text NOT NULL,
+  protocol     text CHECK (protocol IN ('ftps','sftp')),
+  host         text,
+  port         int,
+  username     text,
+  password_enc text,
+  base_path    text,
+  created_at   timestamptz NOT NULL DEFAULT now()
+);
+
+-- Preset → festes Ziel (NULL = Standard-Picdrop aus den Einstellungen).
+ALTER TABLE recipes ADD COLUMN IF NOT EXISTS delivery_target_id uuid
+  REFERENCES delivery_targets(id) ON DELETE SET NULL;
+
+-- Ordner → festes Ziel (optional).
+ALTER TABLE folders ADD COLUMN IF NOT EXISTS delivery_target_id uuid
+  REFERENCES delivery_targets(id) ON DELETE SET NULL;