- Add contract tests for tools.Server and tools.Dispatcher interfaces
(tools_test.go), covering all exported behavior including error paths.
pkg/tools coverage: 0% -> 100%.
- Add contract test for execute.Server (ListTools, CallTool), Decl
factory test, and executeElevated early-exit test. execute coverage:
68% -> 71%.
- Remove Close() from Server and Dispatcher interfaces and all
implementations/callers. These existed for MCP server cleanup which
has been removed.