perf: parallelize DB queries across routes, clean up fitness UI

Parallelize sequential DB queries in 11 API routes and page loaders
using Promise.all — measurements/latest, stats/overview, goal streak,
exercises, sessions, task stats, monthly expenses, icon page, offline-db.

Move calorie tracking out of /fitness/measure (now under /fitness/nutrition
only). Remove fade-in entrance animations from nutrition page.

Progressive streak computation: scan 3 months first, widen only if needed.

Bump versions to 1.1.1 / 0.2.1.

src-tauri/tauri.conf.json

@@ -1,7 +1,7 @@
 {
   "productName": "Bocken",
   "identifier": "org.bocken.app",
-  "version": "0.2.0",
+  "version": "0.2.1",
   "build": {
     "devUrl": "http://192.168.1.4:5173",
     "frontendDist": "https://bocken.org"