Add LSP Dockerfiles for bash, docker, and marksman

- bash-language-server: Prebuilt npm package (190MB)
- docker-language-server: Multi-stage Go build (49.2MB)
- marksman: Debian with libicu72 for .NET runtime (144MB)
- All configured for Crush via stdio communication

dockerfiles/marksman/Dockerfile

@@ -0,0 +1,14 @@
+FROM debian:bookworm-slim
+
+WORKDIR /app
+
+# Install dependencies (wget and icu-libs for marksman)
+RUN apt-get update && apt-get install -y wget libicu72 && \
+    wget -O /usr/local/bin/marksman \
+    https://github.com/artempyanykh/marksman/releases/download/2025-12-13/marksman-linux-x64 \
+    && chmod +x /usr/local/bin/marksman && \
+    apt-get clean && rm -rf /var/lib/apt/lists/*
+
+# Set entrypoint to run LSP server
+ENTRYPOINT ["marksman"]
+CMD ["server"]