feat: Major WhatsApp integration update with Odoo and pause/resume

## Frontend
- Add media display (images, audio, video, docs) in Inbox
- Add pause/resume functionality for WhatsApp accounts
- Fix media URLs to use nginx proxy (relative URLs)

## API Gateway
- Add /accounts/:id/pause and /accounts/:id/resume endpoints
- Fix media URL handling for browser access

## WhatsApp Core
- Add pauseSession() - disconnect without logout
- Add resumeSession() - reconnect using saved credentials
- Add media download and storage for incoming messages
- Serve media files via /media/ static route

## Odoo Module (odoo_whatsapp_hub)
- Add Chat Hub interface with DOLLARS theme (dark, 3-column layout)
- Add WhatsApp/DRRR theme switcher for chat view
- Add "ABRIR CHAT" button in conversation form
- Add send_message_from_chat() method
- Add security/ir.model.access.csv
- Fix CSS scoping to avoid breaking Odoo UI
- Update webhook to handle message events properly

## Documentation
- Add docs/CONTEXTO_DESARROLLO.md with complete project context

## Infrastructure
- Add whatsapp_media Docker volume
- Configure nginx proxy for /media/ route
- Update .gitignore to track src/sessions/ source files

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

odoo_whatsapp_hub/models/whatsapp_message.py

@@ -68,15 +68,23 @@ class WhatsAppMessage(models.Model):
         """Send message via WhatsApp Central API"""
         self.ensure_one()
         account = self.conversation_id.account_id
+        phone_number = self.conversation_id.phone_number
+
+        if not account.external_id:
+            self.write({
+                'status': 'failed',
+                'error_message': 'La cuenta no está vinculada a WhatsApp Central',
+            })
+            return
 
         try:
+            # Use internal endpoint (no auth required)
             response = requests.post(
-                f'{account.api_url}/api/whatsapp/conversations/{self.conversation_id.external_id}/messages',
-                headers=account._get_headers(),
+                f'{account.api_url}/api/whatsapp/internal/odoo/send',
                 json={
-                    'type': self.message_type,
-                    'content': self.content,
-                    'media_url': self.media_url,
+                    'phone_number': phone_number,
+                    'message': self.content,
+                    'account_id': account.external_id,
                 },
                 timeout=30,
             )
@@ -84,7 +92,7 @@ class WhatsAppMessage(models.Model):
             if response.status_code == 200:
                 data = response.json()
                 self.write({
-                    'external_id': data.get('id'),
+                    'external_id': data.get('message_id'),
                     'status': 'sent',
                     'error_message': False,
                 })