fix: port 7 web features and repair the endless-loading screens

Root cause behind most "stuck loading" reports: the backend changed shape
(schedules became an array, location_preferences a string) while the mobile
parser still hard-cast to Map/int. The TypeError was swallowed by a silent
catch that returned null, and screens only handled the success state, so a
parse failure rendered as a permanent spinner. Same class of bug appeared
across service lists via non-null map lookups and a total absence of
request timeouts.

Ported from prosappweb:
- in-app suggestions (POST /suggestions)
- policies/terms from GET /settings/policies
- configurable appointment length (slot_duration_minutes)
- block/unblock calendar slots (POST /services/block)
- GPS city detection on the profile (Nominatim)
- server-side professional search with haversine distance
- retry cooldown after a rejected professional application

Reliability:
- parse schedules array (day_of_week 0=Mon) and string location_preferences
- read times as wall clock, so 08:00 stays 08:00 across timezones
- carry minutes into hours in TimeOfDay.add; a minute-based step used to
  loop forever and freeze the calendar (covered by test/time_slots_test.dart)
- semver update check instead of string equality, which blocked every build
  that did not exactly match the configured version
- request timeouts across all repositories
- surface HTTP >= 400 instead of reporting failed writes as success
- error states with retry instead of an indefinite shimmer

Includes pre-existing uncommitted work from the UI redesign.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

lib/screens/home/home_screen.dart

@@ -5,6 +5,8 @@ import 'package:prosappco/components/general_drawer.dart';
 import 'package:prosappco/screens/lists/professional_pending_service_list.dart';
 import 'package:prosappco/screens/user/user_map_screen.dart';
 
+const _kPrimary = Color(0xFF1565C0);
+
 class HomeScreen extends StatelessWidget {
   const HomeScreen({super.key});
 
@@ -15,19 +17,20 @@ class HomeScreen extends StatelessWidget {
         return SafeArea(
           child: shouldProModeActive(context, state)
               ? Scaffold(
-                  backgroundColor: Theme.of(context).colorScheme.background,
-                  drawer: GeneralDrawer(),
+                  backgroundColor: Theme.of(context).colorScheme.surface,
+                  drawer: const GeneralDrawer(),
                   appBar: AppBar(
                     title: const Text('Solicitudes'),
+                    backgroundColor: _kPrimary,
+                    foregroundColor: Colors.white,
+                    elevation: 0,
                   ),
-                  body: ProfessionalPendingServiceListScreen(),
+                  body: const ProfessionalPendingServiceListScreen(),
                 )
               : Scaffold(
-                  backgroundColor: Theme.of(context).colorScheme.background,
-                  drawer: GeneralDrawer(),
-                  body: const Center(
-                    child: UserMapScreen(),
-                  ),
+                  backgroundColor: Theme.of(context).colorScheme.surface,
+                  drawer: const GeneralDrawer(),
+                  body: const UserMapScreen(),
                 ),
         );
       },