M1: masonry board UI — quick-add, note cards, editor, views

- notes Pinia store (load/create/pin/archive/color/trash/restore/delete) with
  view-aware reconcile; api client patch/del methods.
- colors.ts palette (10 keys → light/dark card + swatch tints).
- QuickAdd (collapsed → expand, title/body/color, click-outside/Esc to save),
  NoteCard (color tint, click-to-edit, hover action bar), NoteEditor modal,
  ColorPicker, inline Icon set (no icon dep).
- BoardView rewrite: Notes/Archive/Trash routes, CSS-columns masonry, Pinned +
  Others sections, per-view empty states, sign-out.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FRgehjoz7Yv8LkUfADxACm

frontend/src/router/index.ts

@@ -10,6 +10,18 @@ const router = createRouter({
       component: () => import("../views/BoardView.vue"),
       meta: { requiresAuth: true },
     },
+    {
+      path: "/archive",
+      name: "archive",
+      component: () => import("../views/BoardView.vue"),
+      meta: { requiresAuth: true },
+    },
+    {
+      path: "/trash",
+      name: "trash",
+      component: () => import("../views/BoardView.vue"),
+      meta: { requiresAuth: true },
+    },
     {
       path: "/login",
       name: "login",