feat: add IDE-support tools to MCP server

[intel352]

Summary

• get_module_schema — returns full ModuleSchema (config fields, types, descriptions, defaults, inputs/outputs) for a given module type
• get_step_schema — returns step type description, config keys with types/descriptions, example YAML
• get_template_functions — returns all 10 template functions with signatures, descriptions, examples
• validate_template_expressions — validates pipeline template expressions for forward refs, self-refs, undefined steps, hyphenated dot-access
• get_config_examples — lists/returns example config files from the example/ directory

Test plan

• 30 tests covering all 5 tools (happy path + error/edge cases)
• golangci-lint clean

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR adds five IDE-support tools to the MCP server to improve the developer experience when authoring workflow YAML configurations. The tools provide schema information, template function documentation, template validation, and access to example configurations.

Changes:

• Adds get_module_schema, get_step_schema, get_template_functions, validate_template_expressions, and get_config_examples tools
• Provides comprehensive schema information including config fields, types, descriptions, and examples
• Implements template expression validation with checks for forward references, undefined steps, and syntax issues
• Includes 30 tests covering happy paths and error cases for all new tools

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 11 comments.

File	Description
mcp/tools.go	Implements 5 new MCP tools with schema retrieval, validation, and documentation capabilities (951 lines)
mcp/tools_test.go	Comprehensive test suite covering all new tools with 30 test cases (788 lines)
mcp/server.go	Registers the new tools in the MCP server initialization

Comments suppressed due to low confidence (2)

mcp/tools_test.go:302

• The test checks for 8 expected functions but the actual implementation has 10 functions (missing trimPrefix and trimSuffix from the expected list). While the test will still pass since it only checks that the listed functions exist, it should verify all functions are present for complete coverage. Consider adding "trimPrefix" and "trimSuffix" to the expectedFunctions list.

	expectedFunctions := []string{"uuid", "uuidv4", "now", "lower", "default", "json", "step", "trigger"}
	for _, expected := range expectedFunctions {
		if !funcNames[expected] {
			t.Errorf("expected function %q not found in list", expected)
		}
	}

mcp/tools_test.go:572

• File permission mode 0640 is inconsistent with the project pattern. In server_test.go line 835, test plugins use 0640, but directories use 0750. For consistency, consider using 0600 for files requiring restrictive permissions or 0644 for readable files.

		if err := os.WriteFile(dir+"/"+f, []byte("# test example\nmodules: []\n"), 0640); err != nil {