Move general tasks + time reqs to Settings; add date adjustments

- Rename 'Category Settings' to 'Settings' (nav, page title, component)
- Move Recurring General Tasks and Time Requirements editing to Settings page
- Planner still loads both for calcRequired calculations
- Add date-specific Adjustments section to Planner: per-date +/- hour
  offsets keyed by YYYY-MM-DD (non-recurring); feed into Required Hours total
- Adjustments row shown in Required Hours tfoot when non-zero

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/api.ts

@@ -1,4 +1,4 @@
-import type { BookingsData, StaffMember, GeneralTask, PickupData, TimeReqs, WorkforceRota } from './types'
+import type { BookingsData, StaffMember, GeneralTask, PickupData, TimeReqs, WorkforceRota, Adjustment } from './types'
 
 const BASE = '/hk-planner/api'
 
@@ -11,6 +11,7 @@ export interface ConfigData {
   tolerance_minutes: number
   workforce_rota: WorkforceRota | null
   workforce_departments: string[]
+  adjustments: Adjustment[]
 }
 
 export interface CategoryConfig {
@@ -116,3 +117,11 @@ export function syncWorkforceRota(start: string, end: string): Promise<Workforce
 export function getWorkforceStaff(): Promise<{ id: string; name: string }[]> {
   return request('/workforce/staff')
 }
+
+export function putAdjustments(adjustments: Adjustment[]): Promise<{ ok: boolean }> {
+  return request('/config/adjustments', {
+    method: 'PUT',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ adjustments }),
+  })
+}