feat: support custom HTTP headers per command

- Allow defining custom headers directly inside routes.json for individual commands.

- Unlock seamless integrations with third-party APIs (OpenAI, Gantry, GitHub) requiring specific authentication keys like Authorization or X-Token.

- Preserve global X-DashCord-Token fallback to ensure backwards compatibility with existing setups.

- Update documentation and example config with custom header usage.

Author: nextgearslab

README.md

@@ -224,6 +224,28 @@ The `body_template` can be **any valid JSON structure** (deeply nested objects,
 * `{{attachment_text}}`: The raw UTF-8 text of the file (great for `.txt` or `.json` uploads).
 * `{{attachment.filename}}`: The original name of the uploaded file.
 
+### 5. Custom HTTP Headers (Optional)
+
+By default, DashCord secures your webhooks using the `X-DashCord-Token` header globally defined in your `.env`. However, if you want to bypass your automation tool and point DashCord *directly* at a third-party API (like OpenAI, Gantry, or GitHub), you can define custom HTTP headers per-command.
+
+```json
+"commands": {
+  "chat": {
+    "endpoint": "https://api.openai.com/v1/chat/completions",
+    "method": "POST",
+    "headers": {
+      "Authorization": "Bearer sk-proj-YourApiKeyHere",
+      "OpenAI-Organization": "org-123456"
+    },
+    "body_template": {
+      "model": "gpt-4",
+      "messages": [{"role": "user", "content": "{{raw}}"}]
+    }
+  }
+}
+```
+*Note: Any custom headers defined in `routes.json` will override the global default token if they share the same key. If omitted, the bot falls back to using the global `.env` secret.*
+
 ---
 
 ## 📦 Default Webhook Payload

bot.py

@@ -668,9 +668,15 @@ def post_to_webhook(command: str, payload: dict) -> dict:
         out_json = _render_body_template(body_template, payload)
 
     headers = {"Content-Type": "application/json"}
+    
     if DASHCORD_SHARED_SECRET:
         headers["X-DashCord-Token"] = DASHCORD_SHARED_SECRET
 
+    custom_headers = cfg.get("headers")
+    if isinstance(custom_headers, dict):
+        for h_key, h_val in custom_headers.items():
+            headers[h_key] = str(h_val)
+
     def parse_response(r: requests.Response) -> dict:
         _dbg("WEBHOOK POST cmd=%s status=%s", command, r.status_code)
 
@@ -1182,7 +1188,6 @@ async def on_message(message: discord.Message):
             await _add_reaction_safe(message, COMMAND_REACTION_SUCCESS)
         else:
             await _add_reaction_safe(message, COMMAND_REACTION_FAIL)
-        # ------------------------------
 
         await send_reply(message.channel, data)
     except Exception as e:

routes.json.example

@@ -33,6 +33,10 @@
       "allowed_users": [987654321098765432],
       "accept_attachments": true,
       "allow_without_command": true,
+      "headers": {
+        "Authorization": "Bearer YOUR_CUSTOM_TOKEN_HERE",
+        "X-Custom-Flag": "true"
+      },
       "body_template": {
         "user_data": {
           "id": "{{discord.user_id}}",