fix(cli): wmill dev --no-browser was a no-op

Cliffy's `.option("--no-browser", ...)` creates an option named
`browser` (boolean, default undefined) that becomes `false` when the
flag is passed. The previous code checked `opts.noBrowser`, which
Cliffy never populates, so the guard silently no-op'd and the browser
always opened. Rename to `browser` and check `=== false` explicitly,
matching the `wmill app dev --no-open` convention.

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

cli/src/commands/dev/dev.ts

@@ -186,7 +186,7 @@ async function listWorkspacePaths(): Promise<WmPathItem[]> {
 export interface DevOpts {
   proxyPort?: number;
   path?: string;
-  noBrowser?: boolean;
+  browser?: boolean;
 }
 
 export async function dev(opts: GlobalOptions & SyncOptions & DevOpts) {
@@ -614,7 +614,7 @@ export async function dev(opts: GlobalOptions & SyncOptions & DevOpts) {
   }
 
   function maybeOpenBrowser(url: string) {
-    if (opts.noBrowser) return;
+    if (opts.browser === false) return;
     try {
       open.default(url).catch((error) => {
         console.error(