Make pages load fast on mobile

- Compress responses: page scripts and styles once (brotli or gzip, in
  memory) and cached immutable; pages and API JSON gzipped as they stream
- Service worker serves content-named assets cache-first
- Load the models modal's data when it opens (cached in localStorage)
  instead of shipping the model catalog in every conversation page
- Lazy-load the Tiptap composer and memoize thread messages
- Import lucide icons directly; twui 0.1.4 drops by-name icons from Button
- bun run start builds the pages minified before serving

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/utils/pick-content-encoding.ts

@@ -0,0 +1,32 @@
+export type ContentEncoding = "br" | "gzip";
+
+type Params = {
+    accept_encoding?: string | null;
+    /**
+     * The encodings the caller can produce, preferred first.
+     */
+    offer?: ContentEncoding[];
+};
+
+/**
+ * The encoding to compress a response with for this `Accept-Encoding`:
+ * the first of `offer` (brotli, then gzip) the client takes, else none. A
+ * coding listed with `q=0` is refused, and `*` takes anything.
+ */
+export default function pickContentEncoding({
+    accept_encoding,
+    offer = ["br", "gzip"],
+}: Params): ContentEncoding | null {
+    if (!accept_encoding) return null;
+
+    const accepted = new Set(
+        accept_encoding
+            .toLowerCase()
+            .split(",")
+            .map((part) => part.trim().split(";").map((piece) => piece.trim()))
+            .filter(([, ...params]) => !params.some((param) => /^q=0(\.0*)?$/.test(param)))
+            .map(([coding]) => coding),
+    );
+
+    return offer.find((encoding) => accepted.has(encoding) || accepted.has("*")) ?? null;
+}