Refactor settings model to separate record-based approach

Restructures tenant settings to use individual records instead of a single document

Decouples settings sections into separate typed interfaces with unique IDs
Modifies data loading and service methods to support new record-based settings
Updates mock data and repository to align with new settings structure

wwwroot/data/tenant-settings.json

@@ -1,9 +1,7 @@
-{
-  "id": "tenant-settings",
-  "syncStatus": "synced",
-  "lastModified": "2025-12-15T10:00:00Z",
-
-  "workweek": {
+[
+  {
+    "id": "workweek",
+    "syncStatus": "synced",
     "presets": {
       "standard": {
         "id": "standard",
@@ -34,8 +32,9 @@
     "defaultPreset": "standard",
     "firstDayOfWeek": 1
   },
-
-  "grid": {
+  {
+    "id": "grid",
+    "syncStatus": "synced",
     "dayStartHour": 6,
     "dayEndHour": 22,
     "workStartHour": 8,
@@ -43,15 +42,17 @@
     "hourHeight": 80,
     "snapInterval": 15
   },
-
-  "timeFormat": {
+  {
+    "id": "timeFormat",
+    "syncStatus": "synced",
     "timezone": "Europe/Copenhagen",
     "locale": "da-DK",
     "use24HourFormat": true
   },
-
-  "views": {
+  {
+    "id": "views",
+    "syncStatus": "synced",
     "availableViews": ["simple", "resource", "team", "department"],
     "defaultView": "simple"
   }
-}
+]