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+# Calendar Settings Audit & Simplification Proposal
+
+## Current State: 41 Settings
+
+The calendar app has 41 settings defined in `CalendarAppSettings`. Only **13** are exposed in the Settings UI. The remaining 28 are either used internally with hardcoded defaults or are dead code.
+
+---
+
+## All Settings by Category
+
+### A. View Settings (9) — Core, keep all
+
+| # | Setting | Type | Default | In UI | Used By |
+|---|---------|------|---------|-------|---------|
+| 1 | `defaultView` | `'week' \| 'month' \| 'agenda'` | `'week'` | Yes | ViewsBar, SettingsModal |
+| 2 | `weekStartsOn` | `0 \| 1` | `1` (Mon) | No | WeekView, MonthView, DateStrip, viewStore |
+| 3 | `showOnlyWeekdays` | `boolean` | `false` | Yes | WeekView, MonthView |
+| 4 | `showWeekNumbers` | `boolean` | `false` | Yes | WeekView |
+| 5 | `timeFormat` | `'24h' \| '12h'` | `'24h'` | Yes | WeekView, formatTime/formatHour |
+| 6 | `filterHoursEnabled` | `boolean` | `false` | Yes | WeekView, useVisibleHours |
+| 7 | `dayStartHour` | `number` | `6` | Yes | WeekView, useVisibleHours |
+| 8 | `dayEndHour` | `number` | `20` | Yes | WeekView, useVisibleHours |
+| 9 | `allDayDisplayMode` | `'header' \| 'block'` | `'header'` | Yes | WeekView |
+
+### B. Header Settings (4) — Not in UI, used by CalendarHeader
+
+| # | Setting | Type | Default | In UI | Used By |
+|---|---------|------|---------|-------|---------|
+| 10 | `headerCompact` | `boolean` | `false` | No | CalendarHeader |
+| 11 | `headerWeekdayFormat` | `'full' \| 'short' \| 'hidden'` | `'full'` | No | CalendarHeader |
+| 12 | `headerShowDate` | `boolean` | `true` | No | CalendarHeader |
+| 13 | `headerAlwaysShowMonth` | `boolean` | `false` | No | CalendarHeader |
+
+### C. DateStrip Settings (8) — Not in UI, used by DateStrip
+
+| # | Setting | Type | Default | In UI | Used By |
+|---|---------|------|---------|-------|---------|
+| 14 | `dateStripShowMoonPhases` | `boolean` | `true` | No | DateStrip |
+| 15 | `dateStripShowEventIndicators` | `boolean` | `true` | No | DateStrip |
+| 16 | `dateStripShowWeekday` | `boolean` | `true` | No | DateStrip |
+| 17 | `dateStripHighlightWeekends` | `boolean` | `true` | No | DateStrip |
+| 18 | `dateStripShowMonthDividers` | `boolean` | `true` | No | DateStrip |
+| 19 | `dateStripCompact` | `boolean` | `false` | No | DateStrip |
+| 20 | `dateStripShowWeekNumbers` | `boolean` | `false` | No | DateStrip |
+| 21 | `dateStripCollapsed` | `boolean` | `false` | No | DateStripFab, Layout |
+
+### D. Tag/Filter Settings (2) — Runtime state, not user preference
+
+| # | Setting | Type | Default | In UI | Used By |
+|---|---------|------|---------|-------|---------|
+| 22 | `tagStripCollapsed` | `boolean` | `true` | No | Layout |
+| 23 | `selectedTagIds` | `string[]` | `[]` | No | MonthView, TagStrip, Layout |
+
+### E. Mode Toggles (3) — Runtime state, not user preference
+
+| # | Setting | Type | Default | In UI | Used By |
+|---|---------|------|---------|-------|---------|
+| 24 | `immersiveModeEnabled` | `boolean` | `false` | No | Layout |
+| 25 | `showTasksInCalendar` | `boolean` | `false` | No | WeekView, Layout (reset on load) |
+| 26 | `sidebarCollapsed` | `boolean` | `true` | No | Layout (reset on load) |
+
+### F. Birthday Settings (2) — In UI
+
+| # | Setting | Type | Default | In UI | Used By |
+|---|---------|------|---------|-------|---------|
+| 27 | `showBirthdays` | `boolean` | `true` | Yes | WeekView, MonthView, Layout |
+| 28 | `showBirthdayAge` | `boolean` | `true` | Yes | WeekView, BirthdayPopover |
+
+### G. Quick View Pill (2) — Not in UI
+
+| # | Setting | Type | Default | In UI | Used By |
+|---|---------|------|---------|-------|---------|
+| 29 | `quickViewPillViews` | `CalendarViewType[]` | `['week','month','agenda']` | No | ViewModePill |
+| 30 | `customDayCount` | `number` | `30` | No | viewStore (agenda range) |
+
+### H. Event Defaults (2) — In UI
+
+| # | Setting | Type | Default | In UI | Used By |
+|---|---------|------|---------|-------|---------|
+| 31 | `defaultEventDuration` | `number` | `60` | Yes | EventForm |
+| 32 | `defaultReminder` | `number` | `15` | Yes | SettingsModal |
+
+### I. Voice Input (1) — In UI
+
+| # | Setting | Type | Default | In UI | Used By |
+|---|---------|------|---------|-------|---------|
+| 33 | `sttLanguage` | `'de' \| 'auto'` | `'de'` | Yes | voice-recording composable |
+
+---
+
+## Simplification Proposal: 41 → 18 Settings
+
+### Principle: Settings should be **user-visible preferences** that persist. Runtime UI state (sidebar open, tag selection) and hardcoded component behavior belong elsewhere.
+
+### Keep as Settings (18)
+
+These are genuine user preferences that should persist across sessions:
+
+| # | Setting | Rationale |
+|---|---------|-----------|
+| 1 | `defaultView` | User choice |
+| 2 | `weekStartsOn` | Regional preference, add to UI |
+| 3 | `showOnlyWeekdays` | User choice |
+| 4 | `showWeekNumbers` | User choice |
+| 5 | `timeFormat` | Regional preference |
+| 6 | `filterHoursEnabled` | User choice |
+| 7 | `dayStartHour` | User choice |
+| 8 | `dayEndHour` | User choice |
+| 9 | `allDayDisplayMode` | User choice |
+| 10 | `showBirthdays` | User choice |
+| 11 | `showBirthdayAge` | User choice |
+| 12 | `defaultEventDuration` | User choice |
+| 13 | `defaultReminder` | User choice |
+| 14 | `sttLanguage` | User choice |
+| 15 | `dateStripShowMoonPhases` | Unique feature, worth keeping as user choice |
+| 16 | `dateStripShowEventIndicators` | Useful toggle |
+| 17 | `dateStripHighlightWeekends` | Useful toggle |
+| 18 | `dateStripCompact` | Layout preference |
+
+### Remove — Convert to Hardcoded Defaults (12)
+
+These are not exposed in any UI and their defaults are always used:
+
+| Setting | Default | Reason to Remove |
+|---------|---------|------------------|
+| `headerCompact` | `false` | Never toggled, no UI |
+| `headerWeekdayFormat` | `'full'` | Never toggled, no UI |
+| `headerShowDate` | `true` | Never toggled, no UI |
+| `headerAlwaysShowMonth` | `false` | Never toggled, no UI |
+| `dateStripShowWeekday` | `true` | Always true, no reason to hide |
+| `dateStripShowMonthDividers` | `true` | Always true, no reason to hide |
+| `dateStripShowWeekNumbers` | `false` | Duplicate of `showWeekNumbers` |
+| `quickViewPillViews` | `['week','month','agenda']` | Only 3 views exist, always all shown |
+| `customDayCount` | `30` | Hardcode in agenda view |
+
+### Remove — Move to Component-Local State (11)
+
+These are runtime UI state, not persistent preferences. They should be `$state()` variables in the components that use them:
+
+| Setting | Current Behavior | Where to Move |
+|---------|-----------------|---------------|
+| `dateStripCollapsed` | Persisted | `$state(false)` in DateStrip/Layout |
+| `tagStripCollapsed` | Persisted | `$state(true)` in Layout |
+| `selectedTagIds` | Persisted | `$state([])` in Layout or a tagFilterStore |
+| `immersiveModeEnabled` | Persisted | `$state(false)` in Layout |
+| `showTasksInCalendar` | Reset to `false` on load | `$state(false)` in Layout |
+| `sidebarCollapsed` | Reset to `true` on load | `$state(true)` in Layout |
+
+**Note:** `selectedTagIds` could arguably persist, but the current behavior (persisting filter state) can confuse users who forget they have filters active. Resetting on load is safer.
+
+---
+
+## Proposed New Interface
+
+```typescript
+export interface CalendarAppSettings extends Record<string, unknown> {
+  // View
+  defaultView: CalendarViewType;
+  weekStartsOn: 0 | 1;
+  showOnlyWeekdays: boolean;
+  showWeekNumbers: boolean;
+  timeFormat: '24h' | '12h';
+  filterHoursEnabled: boolean;
+  dayStartHour: number;
+  dayEndHour: number;
+  allDayDisplayMode: 'header' | 'block';
+
+  // Display
+  showBirthdays: boolean;
+  showBirthdayAge: boolean;
+  dateStripShowMoonPhases: boolean;
+  dateStripShowEventIndicators: boolean;
+  dateStripHighlightWeekends: boolean;
+  dateStripCompact: boolean;
+
+  // Event defaults
+  defaultEventDuration: number;
+  defaultReminder: number;
+
+  // Voice
+  sttLanguage: 'de' | 'auto';
+}
+```
+
+### New Settings UI Sections
+
+| Section | Settings | Currently in UI |
+|---------|----------|-----------------|
+| **Ansicht** | defaultView, weekStartsOn, timeFormat, showOnlyWeekdays, showWeekNumbers | Mostly yes, add weekStartsOn |
+| **Stunden** | filterHoursEnabled, dayStartHour, dayEndHour | Yes |
+| **Anzeige** | allDayDisplayMode, dateStripCompact, dateStripShowMoonPhases, dateStripShowEventIndicators, dateStripHighlightWeekends | Partially |
+| **Termine** | defaultEventDuration, defaultReminder | Yes |
+| **Geburtstage** | showBirthdays, showBirthdayAge | Yes |
+| **Spracheingabe** | sttLanguage | Yes |
+
+---
+
+## Migration Steps
+
+1. Move UI state to component-local `$state()` (sidebarCollapsed, tagStripCollapsed, etc.)
+2. Replace header settings with hardcoded values in CalendarHeader
+3. Replace removed dateStrip settings with hardcoded values in DateStrip
+4. Remove `quickViewPillViews` and `customDayCount` (hardcode)
+5. Update `CalendarAppSettings` interface
+6. Update settings store (remove getters, toggles, cloud sync exclusions)
+7. Update SettingsModal to expose `weekStartsOn` and dateStrip display settings
+8. Add localStorage migration to handle existing users (read old keys, map to new)
+
+---
+
+## Impact Assessment
+
+| Change | Risk | Files Affected |
+|--------|------|----------------|
+| Remove header settings | Low — defaults always used | CalendarHeader.svelte, settings store |
+| Move UI state out | Medium — need to wire up component state | Layout, DateStripFab, TagStrip |
+| Remove quickViewPillViews | Low — only 3 views exist | ViewModePill.svelte |
+| Add weekStartsOn to UI | Low — just add dropdown | SettingsModal, settings page |
+| localStorage migration | Low — one-time migration function | settings store |