feat: package sqlite kv-store backend for stricter browser envs (#23089)

While the current sqlite backend for kv-store works fine in vanilla
browser environments, browser policies can be stricter for extensions.
For example, Chromium's MV3 doesn't accept extensions using `eval` or
freely instantiating `Function`'s. This PR deals with said issues so
that eventual wallet implementers don't have to.

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: mverzilli

yarn-project/kv-store/browser-stubs/buffer.js

@@ -240,6 +240,21 @@ BufferPolyfill.from = function (value, encodingOrOffset, length) {
   );
 };
 
+BufferPolyfill.compare = function (a, b) {
+  if (!ArrayBuffer.isView(a) || !ArrayBuffer.isView(b)) {
+    throw new TypeError('Arguments must be Buffers or Uint8Arrays');
+  }
+  const x = new Uint8Array(a.buffer, a.byteOffset, a.byteLength);
+  const y = new Uint8Array(b.buffer, b.byteOffset, b.byteLength);
+  const len = Math.min(x.length, y.length);
+  for (let i = 0; i < len; i++) {
+    if (x[i] !== y[i]) {
+      return x[i] < y[i] ? -1 : 1;
+    }
+  }
+  return x.length < y.length ? -1 : x.length > y.length ? 1 : 0;
+};
+
 BufferPolyfill.alloc = function (size, fill, encoding) {
   const buf = new BufferPolyfill(size);
   if (fill !== undefined) {

yarn-project/kv-store/package.json

@@ -11,6 +11,16 @@
     "./sqlite-opfs": "./dest/sqlite-opfs/index.js",
     "./stores": "./dest/stores/index.js"
   },
+  "imports": {
+    "#msgpackr": {
+      "browser": "msgpackr/index-no-eval",
+      "default": "msgpackr"
+    },
+    "#ordered-binary": {
+      "browser": "./dest/sqlite-opfs/internal/ordered-binary-browser.js",
+      "default": "ordered-binary"
+    }
+  },
   "scripts": {
     "build": "yarn clean && ../scripts/tsc.sh",
     "build:dev": "../scripts/tsc.sh --watch",

yarn-project/kv-store/src/sqlite-opfs/array.ts

@@ -1,6 +1,6 @@
-import { Encoder } from 'msgpackr';
+import { Encoder } from '#msgpackr';
+import { toBufferKey } from '#ordered-binary';
 import { hash } from 'ohash';
-import { toBufferKey } from 'ordered-binary';
 
 import type { AztecAsyncArray } from '../interfaces/array.js';
 import type { Value } from '../interfaces/common.js';