feat(notes): liens internes, onglet Réseau, living blocks et consentement IA

Rend les liens entre notes visibles et persistants (sync NoteLink au save, auto-save, graphe réseau rafraîchi), ajoute living blocks, Memory Echo, recherche globale, consentement IA explicite et consolide les prototypes design en architectural-grid.

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

memento-note/lib/consent/ai-consent-client.ts

@@ -0,0 +1,39 @@
+const LOCAL_STORAGE_KEY = 'memento-ai-consent-v1'
+
+/**
+ * Reads the persistent AI processing consent value from local storage.
+ * Returns true if consented, false if rejected or not set.
+ */
+export function getLocalStorageAiConsent(): boolean {
+  if (typeof window === 'undefined') return false
+  try {
+    const val = localStorage.getItem(LOCAL_STORAGE_KEY)
+    return val === 'true'
+  } catch {
+    return false
+  }
+}
+
+/**
+ * Writes the persistent AI processing consent value to local storage.
+ */
+export function setLocalStorageAiConsent(value: boolean): void {
+  if (typeof window === 'undefined') return
+  try {
+    localStorage.setItem(LOCAL_STORAGE_KEY, value ? 'true' : 'false')
+  } catch (e) {
+    console.error('[setLocalStorageAiConsent] Failed to write to localStorage:', e)
+  }
+}
+
+/**
+ * Removes the persistent AI processing consent value from local storage.
+ */
+export function removeLocalStorageAiConsent(): void {
+  if (typeof window === 'undefined') return
+  try {
+    localStorage.removeItem(LOCAL_STORAGE_KEY)
+  } catch (e) {
+    console.error('[removeLocalStorageAiConsent] Failed to remove from localStorage:', e)
+  }
+}