Admin UX: light/dark theme, gallery pagination, content modal + delete, openai type

- Light/dark theme toggle persisted in localStorage
- Gallery pagination: page size 50/100/150/200 with prev/next
- Fullscreen modal viewer (image/video/audio) with metadata and delete
- Delete content: DELETE /api/generations/:id removes file (media-dir guarded)
  and journal record; added Journal.deleteById
- Provider types now include openai
- HTML output escaping in UI

NexusAI/packages/admin/src/routes.ts

@@ -12,7 +12,7 @@ import type { AdminContext } from './context.js';
 
 const log = createLogger('admin:api');
 
-const KNOWN_TYPES = ['nordrouter'];
+const KNOWN_TYPES = ['nordrouter', 'openai'];
 
 function errorReply(err: unknown): { statusCode: number; body: { error: string; code: string } } {
   const e = NexusError.from(err);
@@ -150,6 +150,34 @@ export function registerRoutes(app: FastifyInstance, ctx: AdminContext): void {
     };
   });
 
+  app.delete('/api/generations/:id', async (req, reply) => {
+    try {
+      const { id } = req.params as { id: string };
+      const rec = ctx.journal.getById(id);
+      if (!rec) return reply.code(404).send({ error: 'not found', code: 'NOT_FOUND' });
+
+      let fileRemoved = false;
+      if (rec.filePath) {
+        const mediaDir = path.resolve(ctx.config.mediaDir);
+        const resolved = path.resolve(rec.filePath);
+        // Only delete files that live inside the media dir.
+        if (resolved.startsWith(mediaDir + path.sep) && fs.existsSync(resolved)) {
+          try {
+            fs.unlinkSync(resolved);
+            fileRemoved = true;
+          } catch (e) {
+            log.warn('failed to delete file', e instanceof Error ? e.message : String(e));
+          }
+        }
+      }
+      const recordRemoved = ctx.journal.deleteById(id);
+      return { ok: true, fileRemoved, recordRemoved };
+    } catch (err) {
+      const { statusCode, body } = errorReply(err);
+      return reply.code(statusCode).send(body);
+    }
+  });
+
   log.info('routes registered');
 }