refactor: code efficiency improvements (Issues #9-13, #15, #17-20)

Backend:
- Extract shared hard-delete authorization utility (#9)
- Extract Prisma include constants per entity (#11)
- Fix N+1 query pattern in events findAll (#12)
- Extract shared date utility functions (#13)
- Move vehicle utilization filtering to DB query (#15)
- Add ParseBooleanPipe for query params
- Add CurrentDriver decorator + ResolveDriverInterceptor (#20)

Frontend:
- Extract shared form utilities (toDatetimeLocal) and enum labels (#17)
- Replace browser confirm() with styled ConfirmModal (#18)
- Add centralized query-keys.ts constants (#19)
- Clean up unused imports, add useMemo where needed (#19)
- Standardize filter button styling across list pages

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

frontend/src/hooks/useGps.ts

@@ -11,6 +11,7 @@ import type {
   DeviceQrInfo,
 } from '@/types/gps';
 import toast from 'react-hot-toast';
+import { queryKeys } from '@/lib/query-keys';
 
 // ============================================
 // Admin GPS Hooks
@@ -21,7 +22,7 @@ import toast from 'react-hot-toast';
  */
 export function useGpsStatus() {
   return useQuery<GpsStatus>({
-    queryKey: ['gps', 'status'],
+    queryKey: queryKeys.gps.status,
     queryFn: async () => {
       const { data } = await api.get('/gps/status');
       return data;
@@ -35,7 +36,7 @@ export function useGpsStatus() {
  */
 export function useGpsSettings() {
   return useQuery<GpsSettings>({
-    queryKey: ['gps', 'settings'],
+    queryKey: queryKeys.gps.settings,
     queryFn: async () => {
       const { data } = await api.get('/gps/settings');
       return data;
@@ -55,8 +56,8 @@ export function useUpdateGpsSettings() {
       return data;
     },
     onSuccess: () => {
-      queryClient.invalidateQueries({ queryKey: ['gps', 'settings'] });
-      queryClient.invalidateQueries({ queryKey: ['gps', 'status'] });
+      queryClient.invalidateQueries({ queryKey: queryKeys.gps.settings });
+      queryClient.invalidateQueries({ queryKey: queryKeys.gps.status });
       toast.success('GPS settings updated');
     },
     onError: (error: any) => {
@@ -70,7 +71,7 @@ export function useUpdateGpsSettings() {
  */
 export function useGpsDevices() {
   return useQuery<GpsDevice[]>({
-    queryKey: ['gps', 'devices'],
+    queryKey: queryKeys.gps.devices,
     queryFn: async () => {
       const { data } = await api.get('/gps/devices');
       return data;
@@ -84,7 +85,7 @@ export function useGpsDevices() {
  */
 export function useDeviceQr(driverId: string | null) {
   return useQuery<DeviceQrInfo>({
-    queryKey: ['gps', 'devices', driverId, 'qr'],
+    queryKey: driverId ? queryKeys.gps.deviceQr(driverId) : ['gps', 'devices', null, 'qr'],
     queryFn: async () => {
       const { data } = await api.get(`/gps/devices/${driverId}/qr`);
       return data;
@@ -98,7 +99,7 @@ export function useDeviceQr(driverId: string | null) {
  */
 export function useDriverLocations() {
   return useQuery<DriverLocation[]>({
-    queryKey: ['gps', 'locations'],
+    queryKey: queryKeys.gps.locations.all,
     queryFn: async () => {
       const { data } = await api.get('/gps/locations');
       return data;
@@ -112,7 +113,7 @@ export function useDriverLocations() {
  */
 export function useDriverLocation(driverId: string) {
   return useQuery<DriverLocation>({
-    queryKey: ['gps', 'locations', driverId],
+    queryKey: queryKeys.gps.locations.detail(driverId),
     queryFn: async () => {
       const { data } = await api.get(`/gps/locations/${driverId}`);
       return data;
@@ -127,7 +128,7 @@ export function useDriverLocation(driverId: string) {
  */
 export function useDriverStats(driverId: string, from?: string, to?: string) {
   return useQuery<DriverStats>({
-    queryKey: ['gps', 'stats', driverId, from, to],
+    queryKey: queryKeys.gps.stats(driverId, from, to),
     queryFn: async () => {
       const params = new URLSearchParams();
       if (from) params.append('from', from);
@@ -151,9 +152,9 @@ export function useEnrollDriver() {
       return data;
     },
     onSuccess: (data) => {
-      queryClient.invalidateQueries({ queryKey: ['gps', 'devices'] });
-      queryClient.invalidateQueries({ queryKey: ['gps', 'status'] });
-      queryClient.invalidateQueries({ queryKey: ['drivers'] });
+      queryClient.invalidateQueries({ queryKey: queryKeys.gps.devices });
+      queryClient.invalidateQueries({ queryKey: queryKeys.gps.status });
+      queryClient.invalidateQueries({ queryKey: queryKeys.drivers.all });
       if (data.signalMessageSent) {
         toast.success('Driver enrolled! Setup instructions sent via Signal.');
       } else {
@@ -178,10 +179,10 @@ export function useUnenrollDriver() {
       return data;
     },
     onSuccess: () => {
-      queryClient.invalidateQueries({ queryKey: ['gps', 'devices'] });
-      queryClient.invalidateQueries({ queryKey: ['gps', 'status'] });
-      queryClient.invalidateQueries({ queryKey: ['gps', 'locations'] });
-      queryClient.invalidateQueries({ queryKey: ['drivers'] });
+      queryClient.invalidateQueries({ queryKey: queryKeys.gps.devices });
+      queryClient.invalidateQueries({ queryKey: queryKeys.gps.status });
+      queryClient.invalidateQueries({ queryKey: queryKeys.gps.locations.all });
+      queryClient.invalidateQueries({ queryKey: queryKeys.drivers.all });
       toast.success('Driver unenrolled from GPS tracking');
     },
     onError: (error: any) => {
@@ -199,7 +200,7 @@ export function useUnenrollDriver() {
  */
 export function useMyGpsStatus() {
   return useQuery<MyGpsStatus>({
-    queryKey: ['gps', 'me'],
+    queryKey: queryKeys.gps.me.status,
     queryFn: async () => {
       const { data } = await api.get('/gps/me');
       return data;
@@ -212,7 +213,7 @@ export function useMyGpsStatus() {
  */
 export function useMyGpsStats(from?: string, to?: string) {
   return useQuery<DriverStats>({
-    queryKey: ['gps', 'me', 'stats', from, to],
+    queryKey: queryKeys.gps.me.stats(from, to),
     queryFn: async () => {
       const params = new URLSearchParams();
       if (from) params.append('from', from);
@@ -228,7 +229,7 @@ export function useMyGpsStats(from?: string, to?: string) {
  */
 export function useMyLocation() {
   return useQuery<DriverLocation>({
-    queryKey: ['gps', 'me', 'location'],
+    queryKey: queryKeys.gps.me.location,
     queryFn: async () => {
       const { data } = await api.get('/gps/me/location');
       return data;
@@ -249,7 +250,7 @@ export function useUpdateGpsConsent() {
       return data;
     },
     onSuccess: (data) => {
-      queryClient.invalidateQueries({ queryKey: ['gps', 'me'] });
+      queryClient.invalidateQueries({ queryKey: queryKeys.gps.me.status });
       toast.success(data.message);
     },
     onError: (error: any) => {
@@ -267,7 +268,7 @@ export function useUpdateGpsConsent() {
  */
 export function useTraccarSetupStatus() {
   return useQuery<{ needsSetup: boolean; isAvailable: boolean }>({
-    queryKey: ['gps', 'traccar', 'status'],
+    queryKey: queryKeys.gps.traccar.status,
     queryFn: async () => {
       const { data } = await api.get('/gps/traccar/status');
       return data;
@@ -287,8 +288,8 @@ export function useTraccarSetup() {
       return data;
     },
     onSuccess: () => {
-      queryClient.invalidateQueries({ queryKey: ['gps', 'traccar', 'status'] });
-      queryClient.invalidateQueries({ queryKey: ['gps', 'status'] });
+      queryClient.invalidateQueries({ queryKey: queryKeys.gps.traccar.status });
+      queryClient.invalidateQueries({ queryKey: queryKeys.gps.status });
       toast.success('Traccar setup complete!');
     },
     onError: (error: any) => {
@@ -320,7 +321,7 @@ export function useSyncAdminsToTraccar() {
  */
 export function useTraccarAdminUrl() {
   return useQuery<{ url: string; directAccess: boolean }>({
-    queryKey: ['gps', 'traccar', 'admin-url'],
+    queryKey: queryKeys.gps.traccar.adminUrl,
     queryFn: async () => {
       const { data } = await api.get('/gps/traccar/admin-url');
       return data;