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/Dockerfile

@@ -0,0 +1,40 @@
+FROM golang:1.21-alpine AS builder
+
+# Install build dependencies
+RUN apk add --no-cache git make
+
+# Set working directory
+WORKDIR /app
+
+# Copy go mod files
+COPY repo/go.mod repo/go.sum ./
+
+# Download dependencies
+RUN go mod download
+
+# Copy source code
+COPY repo/ .
+
+# Build application
+RUN CGO_ENABLED=0 GOOS=linux go build -ldflags="-w -s" -o webhook
+
+# Final stage
+FROM cloudron/base:3.2.0
+
+# Copy binary from builder
+COPY --from=builder /app/webhook /usr/local/bin/webhook
+
+# Create data directory
+RUN mkdir -p /app/data
+
+# Set permissions
+RUN chmod +x /usr/local/bin/webhook
+
+# Set working directory
+WORKDIR /app
+
+# Expose port
+EXPOSE 9000
+
+# Start application
+CMD ["/usr/local/bin/webhook", "-hooks", "/app/data/hooks.json", "-verbose"]