Filesystem MCP Server with .mcpignore

<!-- Provide a brief description of your changes --> ## Description ## Motivation and Context <!-- Why is this change needed? What problem does it solve? --> ## How Has This Been Tested? <!-- Have you tested this with an LLM client? Which tool calls have you testsed --> ## Breaking Changes <!-- Will users need to update their MCP client configurations? --> ## Types of changes <!-- What types of changes does your code introduce? Put an `x` in all the boxes that apply: --> - [ ] Bug fix (non-breaking change which fixes an issue) - [ ] New feature (non-breaking change which adds functionality) - [ ] Breaking change (fix or feature that would cause existing functionality to change) - [ ] Documentation update ## Additional Comments <!-- Any additional comments you want to add? -->