docs(readme): add brief DB adapters section; feat(db): add portable DB port + browser/server adapters

Author: gary149

.gitignore

@@ -12,6 +12,8 @@ SECRET_CONFIG
 !.env.ci
 !.env
 gcp-*.json
-db
+# Only ignore the top-level database folder used by local Mongo storage
+/db
+packages/**/db
 models/*
-!models/add-your-models-here.txt
+!models/add-your-models-here.txt

README.md

@@ -114,6 +114,26 @@ In which case the url of your DB will be `MONGODB_URL=mongodb://localhost:27017`
 
 Alternatively, you can use a [free MongoDB Atlas](https://www.mongodb.com/pricing) instance for this, Chat UI should fit comfortably within their free tier. After which you can set the `MONGODB_URL` variable in `.env.local` to match your instance.
 
+### DB adapters (Mongo server + IndexedDB browser)
+
+This branch exposes a small, storage‑agnostic DB “port” under `src/lib/db` so the same API can run on the server (MongoDB) or in the browser (IndexedDB via Dexie):
+
+- Server: existing centralized Mongo service at `$lib/server/db` (no change for server routes).
+- Browser: `import { getDB } from "$lib/db"; const db = await getDB();` exposes the same methods (e.g. `db.conversations.insert`, `db.shared.findByHash`).
+
+Example (browser or server):
+
+```ts
+import { getDB } from "$lib/db";
+
+const db = await getDB();
+await db.conversations.updateFields(id, { title: "New title" });
+```
+
+Notes:
+- `openUploadStream` is server‑only; in the browser use existing HTTP upload routes.
+- Browser adapter stores IDs as strings; avoid relying on `instanceof ObjectId` in client code.
+
 ### Hugging Face Access Token
 
 If you use the Hugging Face router, you will need a Hugging Face access token to run Chat UI locally. You can get one from [your Hugging Face profile](https://huggingface.co/settings/tokens).

package-lock.json

@@ -74,6 +74,7 @@
 		"@resvg/resvg-js": "^2.6.2",
 		"autoprefixer": "^10.4.14",
 		"date-fns": "^2.29.3",
+		"dexie": "^4.0.8",
 		"dotenv": "^16.5.0",
 		"file-type": "^21.0.0",
 		"handlebars": "^4.7.8",