Add locations (Filialen) as a grouping layer above resources

Enables multiple barbers/staff bookable at the same location and time
-- previously "resource" conflated "location" and "the thing that
can't double-book itself" into one row, so a Filiale could only ever
have exactly one bookable slot at once.

- New `locations` table; `resources.location_id` with a generic,
  idempotent backfill migration (any resource without a location gets
  one auto-created matching its name -- not a one-off for any single
  client, protects any future resource stuck in the old flat shape too)
- `resources`/`resource_hours`/services keep everything they already
  had (hours, min-notice, max-advance, buffer, the no-overlap
  constraint) scoped to resource_id, not location_id -- two barbers at
  one location must stay independently bookable at the same time
- booking_db.py: new locations CRUD mirroring the existing
  resources/services pattern; create_resource now requires a
  location_id, guarded the same way every other tenant check here is
  (get_location existence check, no real FK -- matches this schema's
  existing no-FK convention throughout)
- app.py: new POST /api/locations provisioning route; POST
  /api/resources now requires location_id
- owner_settings.py + settings.html: new self-service "add a Filiale"
  / "add a barber" UI -- there was previously no way to create a
  resource at all outside the CRM/n8n provisioning API
- public_booking.py + book.html: new Filiale picker (reuses the
  existing wireOptionGroup button-group pattern), filtering the
  Mitarbeiter picker to the selected location -- a single-location
  client sees no extra click, same as before Filialen existed
- owner_booking.py + agenda.html: the Filiale show/hide toggle and
  hide-cancelled toggle (shipped earlier this session) now key off
  location_id instead of resource_id, so hiding a Filiale hides every
  barber's bookings at it; manual-booking dropdown grouped by Filiale
- n8n/onboarding.json: default provisioning now creates a "Hauptfiliale"
  location before its resource (inert until re-imported into the live
  n8n instance)

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

backoffice/app/templates/owner/settings.html

@@ -46,7 +46,9 @@
   {% if error == "invalid_service" %}
     <div class="error">Bitte Name und eine gültige Dauer angeben.</div>
   {% elif error == "invalid_resource" %}
-    <div class="error">Vorlaufzeit, Vorausbuchung und Puffer müssen 0 oder größer sein.</div>
+    <div class="error">Bitte einen Namen angeben; Vorlaufzeit, Vorausbuchung und Puffer müssen 0 oder größer sein.</div>
+  {% elif error == "invalid_location" %}
+    <div class="error">Bitte einen Namen für die Filiale angeben.</div>
   {% elif error == "invalid_hours" %}
     <div class="error">Bitte gültige Öffnungszeiten angeben (Ende nach Beginn).</div>
   {% elif error == "invalid_notify_channel" %}
@@ -95,48 +97,94 @@
     </form>
   </section>
 
-  {% for r in resources %}
+  {% for loc in locations %}
   <section>
-    <h2>Verfügbarkeit — {{ r.name }}</h2>
-    <form class="row" method="post" action="{{ url_for('owner_settings.update_resource', resource_id=r.resource_id) }}">
+    <h2 style="font-size:1.05rem;color:var(--ink);">Filiale — {{ loc.name }}</h2>
+
+    <form class="row" method="post" action="{{ url_for('owner_settings.update_location', location_id=loc.location_id) }}">
       <div class="field">
-        <label>Vorlaufzeit (Min.)</label>
-        <input type="number" name="min_notice_minutes" value="{{ r.min_notice_minutes }}" min="0" required />
+        <label>Name</label>
+        <input type="text" name="name" value="{{ loc.name }}" required />
       </div>
       <div class="field">
-        <label>Vorausbuchung (Tage)</label>
-        <input type="number" name="max_advance_days" value="{{ r.max_advance_days }}" min="0" required />
+        <label>Aktiv</label>
+        <input type="checkbox" name="active" {{ 'checked' if loc.active }} />
       </div>
-      <div class="field">
-        <label>Puffer (Min.)</label>
-        <input type="number" name="buffer_minutes" value="{{ r.buffer_minutes }}" min="0" required />
-      </div>
-      <button type="submit" class="btn btn-small">Speichern</button>
+      <button type="submit" class="btn btn-small">Filiale speichern</button>
     </form>
 
-    <form method="post" action="{{ url_for('owner_settings.update_resource_hours', resource_id=r.resource_id) }}">
-      {% set hours = hours_by_resource.get(r.resource_id, {}) %}
-      {% set day_names = {0: 'Montag', 1: 'Dienstag', 2: 'Mittwoch', 3: 'Donnerstag',
-                           4: 'Freitag', 5: 'Samstag', 6: 'Sonntag'} %}
-      {% for weekday in weekdays %}
-      {% set day_hours = hours.get(weekday) %}
-      <div class="weekday-row">
-        <span class="day-name">{{ day_names[weekday] }}</span>
-        <input type="time" name="opens_at_{{ weekday }}"
-               value="{{ day_hours[0].strftime('%H:%M') if day_hours else '' }}" />
-        <span>&ndash;</span>
-        <input type="time" name="closes_at_{{ weekday }}"
-               value="{{ day_hours[1].strftime('%H:%M') if day_hours else '' }}" />
-        <input type="checkbox" name="closed_{{ weekday }}" id="closed_{{ r.resource_id }}_{{ weekday }}"
-               {{ 'checked' if not day_hours }} />
-        <label for="closed_{{ r.resource_id }}_{{ weekday }}">Geschlossen</label>
+    {% for r in resources_by_location.get(loc.location_id, []) %}
+    <div style="border-top:1px solid var(--line); margin-top:14px; padding-top:14px;">
+      <h2>Mitarbeiter — {{ r.name }}</h2>
+      <form class="row" method="post" action="{{ url_for('owner_settings.update_resource', resource_id=r.resource_id) }}">
+        <div class="field">
+          <label>Name</label>
+          <input type="text" name="name" value="{{ r.name }}" required />
+        </div>
+        <div class="field">
+          <label>Aktiv</label>
+          <input type="checkbox" name="active" {{ 'checked' if r.active }} />
+        </div>
+        <div class="field">
+          <label>Vorlaufzeit (Min.)</label>
+          <input type="number" name="min_notice_minutes" value="{{ r.min_notice_minutes }}" min="0" required />
+        </div>
+        <div class="field">
+          <label>Vorausbuchung (Tage)</label>
+          <input type="number" name="max_advance_days" value="{{ r.max_advance_days }}" min="0" required />
+        </div>
+        <div class="field">
+          <label>Puffer (Min.)</label>
+          <input type="number" name="buffer_minutes" value="{{ r.buffer_minutes }}" min="0" required />
+        </div>
+        <button type="submit" class="btn btn-small">Speichern</button>
+      </form>
+
+      <form method="post" action="{{ url_for('owner_settings.update_resource_hours', resource_id=r.resource_id) }}">
+        {% set hours = hours_by_resource.get(r.resource_id, {}) %}
+        {% set day_names = {0: 'Montag', 1: 'Dienstag', 2: 'Mittwoch', 3: 'Donnerstag',
+                             4: 'Freitag', 5: 'Samstag', 6: 'Sonntag'} %}
+        {% for weekday in weekdays %}
+        {% set day_hours = hours.get(weekday) %}
+        <div class="weekday-row">
+          <span class="day-name">{{ day_names[weekday] }}</span>
+          <input type="time" name="opens_at_{{ weekday }}"
+                 value="{{ day_hours[0].strftime('%H:%M') if day_hours else '' }}" />
+          <span>&ndash;</span>
+          <input type="time" name="closes_at_{{ weekday }}"
+                 value="{{ day_hours[1].strftime('%H:%M') if day_hours else '' }}" />
+          <input type="checkbox" name="closed_{{ weekday }}" id="closed_{{ r.resource_id }}_{{ weekday }}"
+                 {{ 'checked' if not day_hours }} />
+          <label for="closed_{{ r.resource_id }}_{{ weekday }}">Geschlossen</label>
+        </div>
+        {% endfor %}
+        <button type="submit" class="btn btn-small">Öffnungszeiten speichern</button>
+      </form>
+    </div>
+    {% endfor %}
+
+    <form class="row" method="post" action="{{ url_for('owner_settings.create_resource') }}" style="margin-top:14px;">
+      <input type="hidden" name="location_id" value="{{ loc.location_id }}" />
+      <div class="field">
+        <label>Neuer Mitarbeiter</label>
+        <input type="text" name="name" placeholder="Name" required />
       </div>
-      {% endfor %}
-      <button type="submit" class="btn btn-small">Öffnungszeiten speichern</button>
+      <button type="submit" class="btn">Hinzufügen</button>
     </form>
   </section>
   {% endfor %}
 
+  <section>
+    <h2>Neue Filiale</h2>
+    <form class="row" method="post" action="{{ url_for('owner_settings.create_location') }}">
+      <div class="field">
+        <label>Name</label>
+        <input type="text" name="name" placeholder="z. B. Innenstadt" required />
+      </div>
+      <button type="submit" class="btn">Hinzufügen</button>
+    </form>
+  </section>
+
   <section>
     <h2>Buchungen &amp; Benachrichtigung</h2>
     <form class="row" method="post" action="{{ url_for('owner_settings.update_client') }}">