fix(basic-host): use tool display-name precedence in headers

[Michael-WhiteCapData]

Summary

• render the reference host tool-call header with title, then annotations.title, then name
• keep the precedence in a small testable helper
• add regression coverage for all three precedence levels

Closes #767.

Verification

• npm test — 441 passed, 2 platform-specific skipped
• npm run --workspace examples/basic-host build
• prettier --check on changed files
• git diff --check