feat: send song requests to Hermes via webhook

- Add Hermes webhook settings form in /admin/settings (URL + HMAC secret)
- Add /admin/request/<id>/send-to-hermes action
- POST request data to Hermes with V2 HMAC signature and callback URL
- Hermes can POST the generated MusicGPT prompt back to /api/prompt/<id>
- Add test button, update README workflow, bump version to 0.9.0

helpers.py

@@ -409,6 +409,97 @@ def get_ntfy_config():
     }
 
 
+def get_hermes_webhook_config():
+    """Return the Hermes webhook URL and HMAC secret from runtime settings."""
+    cfg = load_booth_settings()
+    return {
+        'url': cfg.get('hermes_webhook_url', '').strip(),
+        'secret': decrypt_value(cfg.get('hermes_webhook_secret', '')) or '',
+    }
+
+
+def set_hermes_webhook_config(url, secret):
+    """Persist Hermes webhook URL and secret (encrypted) to runtime settings."""
+    cfg = load_booth_settings()
+    cfg['hermes_webhook_url'] = url.strip().rstrip('/')
+    if secret:
+        cfg['hermes_webhook_secret'] = encrypt_value(secret)
+    save_booth_settings(cfg)
+
+
+def send_hermes_webhook(rid, req, callback_url=None):
+    """
+    POST a song request payload to the configured Hermes webhook.
+
+    Returns (success: bool, message: str). On success, Hermes receives the
+    customer data and can generate a Suno/MusicGPT prompt. If callback_url is
+    provided, Hermes can POST the generated prompt directly back to
+    /api/prompt/<rid>.
+    """
+    cfg = get_hermes_webhook_config()
+    url = cfg.get('url', '')
+    secret = cfg.get('secret', '')
+    if not url or not secret:
+        return False, 'Hermes webhook is not configured in /admin/settings'
+
+    style_genre = req.get('style_genre') or ''
+    style_parts = [p.strip() for p in style_genre.split(',') if p.strip()]
+    style_sentence = ''
+    if style_parts:
+        parts = []
+        if style_parts[0]:
+            parts.append(f"{style_parts[0]}-era")
+        if len(style_parts) > 1 and style_parts[1]:
+            parts.append(style_parts[1])
+        if len(style_parts) > 2:
+            parts.append(f"with {', '.join(style_parts[2:])} influences")
+        style_sentence = ' '.join(parts)
+
+    def _bool(value):
+        if isinstance(value, bool):
+            return value
+        return bool(int(value or 0))
+
+    payload = {
+        'event_type': 'song_request',
+        'request_id': rid,
+        'email': req.get('email', ''),
+        'name': req.get('name', ''),
+        'pronouns': req.get('pronouns', ''),
+        'hobbies': req.get('hobbies', ''),
+        'notable_facts': req.get('notable_facts', ''),
+        'style_genre': style_sentence or style_genre,
+        'vocal_gender': req.get('vocal_gender', ''),
+        'extra_requests': req.get('extra_requests', ''),
+        'stems_interest': _bool(req.get('stems_interest')),
+        'is_revision': bool(req.get('revision_count', 0)) and bool(req.get('revision_note')),
+        'revision_count': int(req.get('revision_count') or 0),
+        'revision_note': req.get('revision_note', ''),
+        'previous_title': req.get('suno_title', ''),
+        'previous_style': req.get('suno_style', ''),
+        'previous_lyrics': req.get('suno_lyrics', ''),
+        'callback_url': callback_url or '',
+    }
+
+    body = json.dumps(payload, separators=(',', ':')).encode('utf-8')
+    timestamp = str(int(time.time()))
+    sig_data = f"{timestamp}.{body.decode('utf-8')}"
+    signature = hmac.new(secret.encode('utf-8'), sig_data.encode('utf-8'), hashlib.sha256).hexdigest()
+
+    headers = {
+        'Content-Type': 'application/json',
+        'X-Webhook-Signature-V2': signature,
+        'X-Webhook-Timestamp': timestamp,
+    }
+    try:
+        resp = requests.post(url, data=body, headers=headers, timeout=15)
+        if resp.status_code in (200, 202):
+            return True, f"Sent to Hermes (HTTP {resp.status_code})"
+        return False, f"Hermes webhook returned HTTP {resp.status_code}: {resp.text[:200]}"
+    except Exception as e:
+        return False, f"Failed to reach Hermes webhook: {e}"
+
+
 def send_ntfy(message, title='Theme Song Booth', priority='default', tags='bell'):
     """Send a push notification to the configured ntfy topic, if configured."""
     ntfy = get_ntfy_config()