feat: add webhook Cloudron package (API-Gateway)

- Create Dockerfile for webhook (Go application)
- Add CloudronManifest.json with basic configuration
- Include README.md with usage documentation
- Add hooks.json.example configuration template
- Add logo.png (256x256)
- Add CHANGELOG.md for version tracking

Webhook is a lightweight configurable tool written in Go
that allows creating HTTP endpoints (hooks) on your server
for executing configured commands.

Package includes:
- Multi-stage Dockerfile using golang:1.21-alpine
- Cloudron base image for runtime
- Configuration on port 9000
- Localstorage addon for hooks.json
- 256MB memory limit

💘 Generated with Crush

Assisted-by: GLM-4.7 via Crush <crush@charm.land>

Package-Workspace/API-Gateway/webhook/README.md

@@ -0,0 +1,75 @@
+# Webhook Cloudron Package
+
+## Description
+
+Webhook is a lightweight configurable tool written in Go that allows you to easily create HTTP endpoints (hooks) on your server, which you can use to execute configured commands.
+
+## Features
+
+- Define HTTP endpoints that execute commands on your server
+- Pass data from HTTP requests to your commands
+- Specify rules that must be satisfied for hooks to trigger
+- Supports JSON and YAML configuration files
+- Trigger rules for security (secrets, headers, etc.)
+- Hot-reload configuration without restart
+- Support for multipart form data
+- Template support for request values
+
+## Configuration
+
+The webhook application reads configuration from `/app/data/hooks.json` (or `/app/data/hooks.yaml`).
+
+### Example Configuration
+
+```json
+[
+  {
+    "id": "redeploy-webhook",
+    "execute-command": "/var/scripts/redeploy.sh",
+    "command-working-directory": "/var/webhook",
+    "trigger-rule": {
+      "and": [
+        {
+          "match": {
+            "type": "payload-hmac-sha1",
+            "secret": "mysecret",
+            "parameter": {
+              "source": "header",
+              "name": "X-Hub-Signature"
+            }
+          }
+        }
+      ]
+    }
+  }
+]
+```
+
+See [webhook documentation](https://github.com/adnanh/webhook/tree/master/docs) for detailed configuration options.
+
+## Usage
+
+1. Install the webhook app on Cloudron
+2. Navigate to the File Manager
+3. Create or edit `hooks.json` in the `/app/data` directory
+4. Restart the app to apply configuration changes
+5. Access your webhook endpoints at `http://your-app.cloudron.app/hooks/{hook-id}`
+
+## Documentation
+
+For more information on configuring webhooks, visit:
+- [Hook Definition](https://github.com/adnanh/webhook/blob/master/docs/Hook-Definition.md)
+- [Hook Examples](https://github.com/adnanh/webhook/blob/master/docs/Hook-Examples.md)
+- [Hook Rules](https://github.com/adnanh/webhook/blob/master/docs/Hook-Rules.md)
+- [Webhook Parameters](https://github.com/adnanh/webhook/blob/master/docs/Webhook-Parameters.md)
+
+## Security Considerations
+
+- Always use trigger rules to secure your hooks
+- Never expose sensitive commands without proper authentication
+- Use HMAC signatures for verifying webhook sources
+- Consider IP-based rules for additional security
+
+## Upstream
+
+[GitHub Repository](https://github.com/adnanh/webhook)