feat: Spec product version, build bake, Admin UI label.

Resolve VERSION from EventHubSpec; VITE_APP_BUILD from run_number; show Admin UI / API as version.build (sha).

Co-authored-by: Cursor <cursoragent@cursor.com>

src/api/healthApi.ts

@@ -4,6 +4,7 @@ export type AdminHealthInfo = {
     status: string;
     service?: string;
     version?: string;
+    build?: number;
     git_sha?: string;
     built_at?: string;
 };