fix: improve accessibility and tokenize remaining hardcoded CSS values

- FAB focus ring: double-ring pattern replacing invisible #fff outline
- forced-colors media query for Windows High Contrast Mode
- New tokens: --color-accent-secondary, --content-max-width-narrow, --cal-hour-height
- Apple sync logo uses semantic tokens for correct dark mode inversion
- Sidebar logo gradient references token instead of hardcoded #7C5CFC

package.json

@@ -1,6 +1,6 @@
 {
   "name": "oikos",
-  "version": "0.19.1",
+  "version": "0.19.2",
   "description": "Self-hosted family planner - calendar, tasks, shopping, meal planning, budget and more. Private, open-source, no subscription.",
   "main": "server/index.js",
   "type": "module",