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>

packages/chat_repository/lib/src/repositories/api_chat_repository.dart

@@ -4,6 +4,8 @@ import 'package:http/http.dart' as http;
 import 'package:shared_preferences/shared_preferences.dart';
 import 'package:chat_repository/chat_repository.dart';
 
+const _kHttpTimeout = Duration(seconds: 20);
+
 const _base = 'https://backend.prosapp.co/api/v1';
 
 /// API-backed replacement for FirebaseChatRepository.
@@ -57,7 +59,7 @@ class ApiChatRepository {
     final res = await http.post(
       Uri.parse('$_base/chat/start/$professionalId'),
       headers: await _headers(),
-    );
+    ).timeout(_kHttpTimeout);
     final data = jsonDecode(res.body) as Map<String, dynamic>;
     return _chatFromApi(data);
   }
@@ -81,7 +83,7 @@ class ApiChatRepository {
       final res = await http.get(
         Uri.parse('$_base/chat/$chatId/messages'),
         headers: await _headers(),
-      );
+      ).timeout(_kHttpTimeout);
       if (res.statusCode == 404) return null;
       final messages = jsonDecode(res.body) as List? ?? [];
       return ChatEntity(
@@ -102,7 +104,7 @@ class ApiChatRepository {
       Uri.parse('$_base/chat/$chatId/message'),
       headers: await _headers(),
       body: jsonEncode({'content': message.content}),
-    );
+    ).timeout(_kHttpTimeout);
   }
 
   /// Get all chats for the current user.
@@ -111,7 +113,7 @@ class ApiChatRepository {
       final res = await http.get(
         Uri.parse('$_base/chat/my'),
         headers: await _headers(),
-      );
+      ).timeout(_kHttpTimeout);
       final data = jsonDecode(res.body) as List? ?? [];
       return data.map((e) => _chatFromApi(e as Map<String, dynamic>)).toList();
     } catch (_) {