feat(client): set dynamic page title based on content

- add usePageTitle hook that writes '<title> | Liqa' to document.title
- list pages use section name; detail pages use entity name once loaded
- create/edit pages use static action title, edit includes entity name

client/src/hooks/usePageTitle.ts

@@ -0,0 +1,17 @@
+import { useEffect } from 'react';
+
+const APP_NAME = 'Liqa';
+
+/**
+ * Sets document.title to "<title> | Liqa" for the current page.
+ * Pass undefined or empty string to fall back to just "Liqa".
+ */
+export function usePageTitle(title: string | null | undefined): void {
+  useEffect(() => {
+    const prev = document.title;
+    document.title = title ? `${title} | ${APP_NAME}` : APP_NAME;
+    return () => {
+      document.title = prev;
+    };
+  }, [title]);
+}