feat: implement PDF generation and update Dockerfile

- Add PDF generation using go-pdf/fpdf (Pure Go library)
- Walk markdown AST and render directly to PDF
- Update Dockerfile to include themes directory and config
- Fix ENTRYPOINT format for serve mode

Co-Authored-By: Claude (glm-5) <noreply@anthropic.com>

dockerfile

@@ -19,7 +19,7 @@ RUN CGO_ENABLED=0 GOOS=${GO_OS} GOARCH=${GO_ARCH} \
     go build \
     -installsuffix cgo \
     -ldflags="-w -s -X 'main.APP_VERSION=${APP_VERSION}' -X 'main.COMMIT_ID=$(git log HEAD --oneline | awk '{print $1}' | head -n1)'" \
-    --o /gocv
+    -o /gocv
 
 # Stage 2 · scratch image
 FROM scratch
@@ -28,6 +28,13 @@ FROM scratch
 COPY --from=build /gocv /gocv
 # Copy the certificates - in case of fetches
 COPY --from=build /etc/ssl/certs/ca-certificates.crt /etc/ssl/cert.pem
+# Copy themes for templates
+COPY --from=build $GOPATH/src/${GIT_HOST}/${REPO_ORG}/${REPO_NAME}/themes /themes
+# Copy default config
+COPY --from=build $GOPATH/src/${GIT_HOST}/${REPO_ORG}/${REPO_NAME}/config.yaml /config.yaml
+
+# Create content and output directories
+# Note: In scratch image, we need to mount these at runtime
 
 # Execute the binary
-ENTRYPOINT ["/gocv serve"]
+ENTRYPOINT ["/gocv", "serve"]