Update README with Docker webhook setup instructions

Documents the host.docker.internal approach for Gitea running in
a Docker container, including docker-compose config and gotchas.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

README.md

@@ -64,7 +64,7 @@ You can re-trigger processing by editing the file to restore the original `BLIGH
 ```bash
 # 1. Clone this repo onto the machine that will run the listener
 git clone <this-repo-url>
-cd Blight_Reader
+cd BLIGHT--CUE
 
 # 2. Create and activate a virtual environment
 python3 -m venv .venv
@@ -84,7 +84,7 @@ cp .env.example .env
 Edit `.env` with your values:
 
 | Variable         | Description                                                         |
-|---|---|
+| ---------------- | ------------------------------------------------------------------- |
 | `GITEA_URL`      | Base URL of your Gitea instance, no trailing slash                  |
 | `GITEA_TOKEN`    | Personal access token from Gitea → Settings → Applications          |
 | `GEMINI_API_KEY` | API key from [Google AI Studio](https://aistudio.google.com/apikey) |
@@ -125,12 +125,45 @@ WantedBy=multi-user.target
 
 ## Registering the Webhook in Gitea
 
+### If Gitea runs in Docker
+
+Gitea containers cannot reach `localhost` on the host directly. The recommended approach is to use `host.docker.internal`, which Docker resolves to the host machine's IP.
+
+**1. Add `extra_hosts` to your Gitea `docker-compose.yml`:**
+
+```yaml
+services:
+  gitea:
+    image: gitea/gitea:latest
+    # ... your existing config ...
+    extra_hosts:
+      - "host.docker.internal:host-gateway"
+```
+
+**2. Restart Gitea:**
+
+```bash
+docker compose down && docker compose up -d
+```
+
+**3. Register the webhook using `host.docker.internal` as the host** (see below), with the Target URL set to:
+
+```
+http://host.docker.internal:5010/webhook
+```
+
+> **Note:** If Gitea is not running when CUE fires, or CUE is not running when Gitea sends a webhook, the delivery will fail. You can use the **Redeliver** button in the webhook's delivery history to retry without needing to push again.
+
+---
+
+### Registering the Webhook
+
 Do this for **each repository** you want BLIGHT: CUE to watch.
 
 1. Open the repository in Gitea.
 2. Go to **Settings** → **Webhooks** → **Add Webhook** → **Gitea**.
 3. Set the fields:
-   - **Target URL**: `http://<your-machine-ip>:5010/webhook`
+   - **Target URL**: `http://host.docker.internal:5010/webhook` (Docker) or `http://<host-ip>:5010/webhook` (non-Docker)
    - **HTTP Method**: POST
    - **Content Type**: `application/json`
    - **Secret**: the same value as `WEBHOOK_SECRET` in your `.env`