build: configure multi-entry Vite build for reader

- Add reader.ts as second entry point alongside main.ts in vite.config.ts
- Set assetsDir to empty string to output chunks to /static/ root
- Remove reader-shell import from main.ts (loaded separately via reader.js)
- Update .gitignore to exclude web/static/assets/*.js chunks
- Update Bruno environment with new test IDs

bruno/environments/Bookhoard.yml

@@ -3,7 +3,7 @@ variables:
   - name: base_url
     value: http://localhost:8765
   - name: media_item_id
-    value: 18a08a9f-4683-4250-8eec-11983753b6dc
+    value: 8bd13107-e1e5-4357-b893-bfc77f1e087c
   - name: fake_book_id
     value: 123e4567-e89b-12d3-a456-426614174000
   - name: user_id
@@ -13,7 +13,7 @@ variables:
   - name: note_id
     value: 7710a602-g29b-61d4-c716-446655440002
   - name: library_id
-    value: dd03d719-76c8-4398-93ec-9258d2becf85
+    value: 7e970863-bcd9-4559-a416-e8d7c2af92c5
   - name: job_id
     value: d5554991-1a13-4f60-9a70-82d19ed1abe2
   - name: rating