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/utils/time_of_day_utils.dart

@@ -2,13 +2,14 @@ import 'package:flutter/material.dart';
 import 'package:prosappco/utils/time_of_day_extension.dart';
 
 class TimeOfDayUtils {
-  static List<TimeOfDay> genRanges(TimeOfDay timeStart, TimeOfDay timeEnd) {
+  static List<TimeOfDay> genRanges(TimeOfDay timeStart, TimeOfDay timeEnd,
+      {int stepMinutes = 30}) {
+    final step = stepMinutes.clamp(5, 480);
     List<TimeOfDay> ranges = [];
     TimeOfDay current = timeStart;
     while (current.isBefore(timeEnd)) {
       ranges.add(current);
-      // Sumar 2 horas al objeto DateTime
-      current = current.add(hour: 2);
+      current = current.add(minute: step);
     }
     return ranges;
   }