feat: expose archive entries in fsScanner

- Añade `scanDirectory` support para listar entradas internas de ZIP/7z
- Añade test unitario que mockea `archiveReader.listArchiveEntries`
- Añade límite configurable `ARCHIVE_MAX_ENTRIES` y comprobación básica de seguridad

backend/src/services/fsScanner.ts

@@ -13,9 +13,13 @@
 import path from 'path';
 import { promises as fsPromises } from 'fs';
 import { detectFormat } from '../lib/fileTypeDetector';
+import { listArchiveEntries } from './archiveReader';
+
+const ARCHIVE_MAX_ENTRIES = Number(process.env.ARCHIVE_MAX_ENTRIES) || 1000;
 
 export async function scanDirectory(dirPath: string): Promise<any[]> {
   const results: any[] = [];
+  let archiveEntriesAdded = 0;
 
   async function walk(dir: string) {
     const entries = await fsPromises.readdir(dir, { withFileTypes: true });
@@ -43,6 +47,35 @@ export async function scanDirectory(dirPath: string): Promise<any[]> {
           format,
           isArchive,
         });
+
+        if (isArchive) {
+          try {
+            const entries = await listArchiveEntries(full);
+
+            for (const e of entries) {
+              if (archiveEntriesAdded >= ARCHIVE_MAX_ENTRIES) break;
+              if (!e || !e.name) continue;
+              // avoid path traversal or absolute paths
+              if (e.name.includes('..') || path.isAbsolute(e.name)) continue;
+
+              results.push({
+                path: `${full}::${e.name}`,
+                containerPath: full,
+                entryPath: e.name,
+                filename: path.basename(e.name),
+                name: e.name,
+                size: e.size,
+                format: detectFormat(e.name),
+                isArchive: false,
+                isArchiveEntry: true,
+              });
+
+              archiveEntriesAdded++;
+            }
+          } catch (err) {
+            // ignore archive listing errors
+          }
+        }
       }
     }
   }

backend/tests/services/fsScanner.archiveEntries.spec.ts

@@ -0,0 +1,35 @@
+import path from 'path';
+import os from 'os';
+import { promises as fs } from 'fs';
+import { afterEach, it, expect, vi } from 'vitest';
+
+vi.mock('../../src/services/archiveReader', () => ({ listArchiveEntries: vi.fn() }));
+
+import scanDirectory from '../../src/services/fsScanner';
+import { listArchiveEntries } from '../../src/services/archiveReader';
+
+afterEach(() => vi.restoreAllMocks());
+
+it('expone entradas internas de archivos como items virtuales', async () => {
+  const tmpDir = await fs.mkdtemp(path.join(os.tmpdir(), 'fsScanner-test-'));
+  const collectionFile = path.join(tmpDir, 'collection.zip');
+  await fs.writeFile(collectionFile, '');
+
+  (listArchiveEntries as unknown as vi.Mock).mockResolvedValue([
+    { name: 'inner/rom1.bin', size: 1234 },
+  ]);
+
+  const results = await scanDirectory(tmpDir);
+
+  const expectedPath = `${collectionFile}::inner/rom1.bin`;
+  const found = results.find((r: any) => r.path === expectedPath);
+
+  expect(found).toBeDefined();
+  expect(found.isArchiveEntry).toBe(true);
+  expect(found.containerPath).toBe(collectionFile);
+  expect(found.entryPath).toBe('inner/rom1.bin');
+  expect(found.filename).toBe('rom1.bin');
+  expect(found.format).toBe('bin');
+
+  await fs.rm(tmpDir, { recursive: true, force: true });
+});