fix: brainstorm infinite loop, ghost cursor, embedding ::vector cast, semantic search, billing stats, usage meter accordion

- Fix useBrainstormSocket: stable guestId via useRef, remove setState in cleanup
- Fix GhostCursor: direct DOM manipulation via refs, no useState re-renders
- Fix all SQL embedding queries: add ::vector cast on text columns
- Fix embedding truncation to 15000 chars (under 8192 token limit)
- Fix NoteEmbedding INSERT: remove non-existent updatedAt column
- Fix billing page: show all quota stats in grid instead of single metric
- Fix usage meter: accordion expand/collapse, per-feature detail
- Fix semantic search: rebuild 103 note embeddings, ::vector cast on vectorSearch
- Fix brainstorm expand/manual-idea/create: ::vector cast on embedding SQL

memento-note/components/note-editor/note-editor-dialog.tsx

@@ -116,7 +116,7 @@ export function NoteEditorDialog({ onClose }: NoteEditorDialogProps) {
                 noteId={note.id}
                 onOpenNote={(noteId: string) => {
                   onClose()
-                  window.location.href = `/?note=${noteId}`
+                  window.location.href = `/home?note=${noteId}`
                 }}
                 onCompareNotes={(noteIds: string[]) => {
                   Promise.all(noteIds.map(async (id: string) => {
@@ -296,7 +296,7 @@ export function NoteEditorDialog({ onClose }: NoteEditorDialogProps) {
           notes={state.comparisonNotes}
           onOpenNote={(noteId: string) => {
             onClose()
-            window.location.href = `/?note=${noteId}`
+            window.location.href = `/home?note=${noteId}`
           }}
         />
       )}