feat: add Docker support for cross-platform easy setup

Implements comprehensive Docker support to eliminate Python version and dependency concerns.
Users can now run the MCP server in a container with automatic path translation between
host and container filesystems.

Key features:
- Dockerfile with multi-architecture support (amd64/arm64)
- Automatic path translation using WORKSPACE_ROOT environment variable
- Setup scripts for all platforms (Bash, CMD, PowerShell)
- GitHub Actions workflow for automated Docker Hub publishing
- Secure non-root container execution
- Read-only volume mounts by default

The setup process is now simplified to:
1. Run setup-docker-env script to generate .env and Claude config
2. Build the Docker image
3. Copy generated config to Claude Desktop

No Python installation or virtual environment management required.

Fixes #3

Co-Authored-By: Claude <noreply@anthropic.com>

utils/file_utils.py

@@ -24,18 +24,29 @@ from typing import List, Optional, Tuple, Set
 
 from .token_utils import estimate_tokens, MAX_CONTEXT_TOKENS
 
+# Get workspace root for Docker path translation
+# When running in Docker with a mounted workspace, WORKSPACE_ROOT contains
+# the host path that corresponds to /workspace in the container
+WORKSPACE_ROOT = os.environ.get("WORKSPACE_ROOT")
+CONTAINER_WORKSPACE = Path("/workspace")
+
 # Get project root from environment or use current directory
 # This defines the sandbox directory where file access is allowed
 #
 # Security model:
 # 1. If MCP_PROJECT_ROOT is explicitly set, use it as a sandbox
-# 2. If not set, allow access to user's home directory and below
-# 3. Never allow access to system directories outside home
+# 2. If not set and in Docker (WORKSPACE_ROOT exists), use /workspace
+# 3. Otherwise, allow access to user's home directory and below
+# 4. Never allow access to system directories outside home
 env_root = os.environ.get("MCP_PROJECT_ROOT")
 if env_root:
     # If explicitly set, use it as sandbox
     PROJECT_ROOT = Path(env_root).resolve()
     SANDBOX_MODE = True
+elif WORKSPACE_ROOT and CONTAINER_WORKSPACE.exists():
+    # Running in Docker with workspace mounted
+    PROJECT_ROOT = CONTAINER_WORKSPACE
+    SANDBOX_MODE = True
 else:
     # If not set, default to home directory for safety
     # This allows access to any file under the user's home directory
@@ -130,6 +141,45 @@ CODE_EXTENSIONS = {
 }
 
 
+def translate_docker_path(path_str: str) -> str:
+    """
+    Translate host paths to container paths when running in Docker.
+    
+    When running in Docker with WORKSPACE_ROOT set, this function translates
+    absolute paths from the host filesystem to their equivalent paths inside
+    the container. This enables seamless operation where Claude sends host
+    paths but the server runs in a container.
+    
+    Args:
+        path_str: Original path string from the client
+        
+    Returns:
+        Translated path string (unchanged if not in Docker mode)
+    """
+    if not WORKSPACE_ROOT or not CONTAINER_WORKSPACE.exists():
+        # Not running in Docker mode, return path unchanged
+        return path_str
+    
+    try:
+        # Resolve both paths to handle different path formats (forward/backslashes)
+        workspace_root_path = Path(WORKSPACE_ROOT).resolve()
+        host_path = Path(path_str).resolve()
+        
+        # Get the relative path from workspace root
+        relative_path = host_path.relative_to(workspace_root_path)
+        
+        # Construct container path using forward slashes (Linux format in container)
+        container_path = CONTAINER_WORKSPACE / relative_path
+        return container_path.as_posix()
+        
+    except ValueError:
+        # Path is not within the workspace root, return unchanged
+        return path_str
+    except Exception:
+        # Any other error (invalid path, etc.), return unchanged
+        return path_str
+
+
 def resolve_and_validate_path(path_str: str) -> Path:
     """
     Validates that a path is absolute and resolves it.
@@ -149,6 +199,9 @@ def resolve_and_validate_path(path_str: str) -> Path:
         ValueError: If path is not absolute
         PermissionError: If path is outside allowed directory
     """
+    # Translate Docker paths if necessary
+    path_str = translate_docker_path(path_str)
+    
     # Create a Path object from the user-provided path
     user_path = Path(path_str)