fix: Safari < 18 glass UI - webkit backdrop-filter @supports fallback

- All @supports checks extended to include or (-webkit-backdrop-filter: blur(1px))
  so Safari < 18 (which only recognizes the -webkit- prefix) no longer skips
  the entire @supports block and receives no glass styles at all
- Non-blur glass styles (background-color, border, box-shadow) moved outside
  @supports blocks - always active on all browsers regardless of blur support
- Capsule buttons, specular highlights, glass borders and shadows now visible
  on all devices, blur effects added on top where supported

package.json

@@ -1,6 +1,6 @@
 {
   "name": "oikos",
-  "version": "0.17.2",
+  "version": "0.17.3",
   "description": "Self-hosted family planner - calendar, tasks, shopping, meal planning, budget and more. Private, open-source, no subscription.",
   "main": "server/index.js",
   "type": "module",