feat: implement browser extension UI with WebAssembly integration

extension/dist/manifest.json

@@ -0,0 +1,36 @@
+{
+  "manifest_version": 3,
+  "name": "Modular Vault Extension",
+  "version": "0.1.0",
+  "description": "Cross-browser modular vault for cryptographic operations and scripting.",
+  "action": {
+    "default_popup": "popup/index.html",
+    "default_icon": {
+      "16": "assets/icon-16.png",
+      "32": "assets/icon-32.png",
+      "48": "assets/icon-48.png",
+      "128": "assets/icon-128.png"
+    }
+  },
+  "background": {
+    "service_worker": "background/index.js",
+    "type": "module"
+  },
+  "permissions": [
+    "storage",
+    "scripting"
+  ],
+  "host_permissions": [],
+  "icons": {
+    "16": "assets/icon-16.png",
+    "32": "assets/icon-32.png",
+    "48": "assets/icon-48.png",
+    "128": "assets/icon-128.png"
+  },
+  "web_accessible_resources": [
+    {
+      "resources": ["wasm/*.wasm", "wasm/*.js"],
+      "matches": ["<all_urls>"]
+    }
+  ]
+}