refactor: extract shared validation and reduce duplication

- Extract tool_types validation to shared module (validate_compose_yaml, check_port_exposed, validate_required_variables)
- Extract _get_user and _get_owned_project to auth/dependencies.py
- Create useAsyncData hook and apply to 6 pages
- Create extractErrorMessage utility
- TypeScript and build pass

apps/web/src/hooks/use-async-data.ts

@@ -0,0 +1,42 @@
+import { useCallback, useEffect, useState } from "react";
+
+type AsyncStatus = "idle" | "loading" | "ready" | "error";
+
+interface UseAsyncDataResult<T> {
+  data: T | null;
+  status: AsyncStatus;
+  error: string | null;
+  reload: () => void;
+}
+
+export function useAsyncData<T>(
+  fetcher: () => Promise<T>,
+  deps: React.DependencyList = []
+): UseAsyncDataResult<T> {
+  const [data, setData] = useState<T | null>(null);
+  const [status, setStatus] = useState<AsyncStatus>("idle");
+  const [error, setError] = useState<string | null>(null);
+
+  const load = useCallback(async () => {
+    setStatus("loading");
+    setError(null);
+    try {
+      const result = await fetcher();
+      setData(result);
+      setStatus("ready");
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "Failed to load data");
+      setStatus("error");
+    }
+  }, deps);
+
+  const reload = useCallback(() => {
+    void load();
+  }, [load]);
+
+  useEffect(() => {
+    void load();
+  }, [load]);
+
+  return { data, status, error, reload };
+}