chore(frontend): introduce prettier + eslint and prune unused code

- Add Prettier 3 with prettier-plugin-organize-imports (sorts/removes unused imports)
- Add ESLint 10 flat config with typescript-eslint + eslint-plugin-vue + eslint-config-prettier
- Add root scripts: format, format:check, lint, lint:fix
- Reformat 257 files across admin-web, ops-web, desktop-client, packages
- Remove unused locals/exports flagged by --noUnusedLocals/--noUnusedParameters
- Fix duplicate localTabLabel key, surrogate-pair regex u-flag, NBSP literal in regex
- Skip server/ (Go) and apps/browser-extension/ (deprecated per ADR)

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

apps/desktop-client/src/main/runtime-events.ts

@@ -1,12 +1,12 @@
-type RuntimeInvalidationReason = "account-health";
+type RuntimeInvalidationReason = 'account-health'
 
 type RuntimeInvalidationListener = (event: {
-  reason: RuntimeInvalidationReason;
-  at: number;
-  accountId?: string;
-}) => void;
+  reason: RuntimeInvalidationReason
+  at: number
+  accountId?: string
+}) => void
 
-const listeners = new Set<RuntimeInvalidationListener>();
+const listeners = new Set<RuntimeInvalidationListener>()
 
 export function emitRuntimeInvalidated(
   reason: RuntimeInvalidationReason,
@@ -16,23 +16,23 @@ export function emitRuntimeInvalidated(
     reason,
     at: Date.now(),
     ...details,
-  } as const;
+  } as const
 
   for (const listener of listeners) {
     try {
-      listener(event);
+      listener(event)
     } catch (error) {
-      console.warn("[desktop-runtime] invalidation listener failed", {
+      console.warn('[desktop-runtime] invalidation listener failed', {
         reason,
         message: error instanceof Error ? error.message : String(error),
-      });
+      })
     }
   }
 }
 
 export function onRuntimeInvalidated(listener: RuntimeInvalidationListener): () => void {
-  listeners.add(listener);
+  listeners.add(listener)
   return () => {
-    listeners.delete(listener);
-  };
+    listeners.delete(listener)
+  }
 }