Add Docker image support with distroless container

- Dockerfile: distroless base (glibc) for CGO binary
- GoReleaser: Docker build + push to ghcr.io/lukaszraczylo/filepuff-mcp
- Cosign signing for Docker manifests

.gitignore

@@ -1,3 +1,4 @@
 TODO.md
 bin/mcp-filepuff
 mcp-filepuff
+dist/

.goreleaser.yaml

@@ -109,6 +109,19 @@ release:
     ```
 
 
+dockers:
+  - image_templates:
+      - "ghcr.io/lukaszraczylo/filepuff-mcp:{{ .Tag }}"
+      - "ghcr.io/lukaszraczylo/filepuff-mcp:latest"
+    ids:
+      - mcp-filepuff-cgo
+    use: buildx
+    build_flag_templates:
+      - "--platform=linux/amd64"
+    goarch: amd64
+    goos: linux
+    dockerfile: Dockerfile
+
 signs:
   - cmd: cosign
     signature: "${artifact}.sigstore.json"
@@ -120,4 +133,13 @@ signs:
     artifacts: checksum
     output: true
 
+docker_signs:
+  - cmd: cosign
+    artifacts: manifests
+    output: true
+    args:
+      - "sign"
+      - "--yes"
+      - "${artifact}"
+
 

Dockerfile

@@ -0,0 +1,3 @@
+FROM gcr.io/distroless/base-debian12:nonroot
+COPY mcp-filepuff /usr/local/bin/mcp-filepuff
+ENTRYPOINT ["mcp-filepuff"]