feat(mcp): expose show_uncovered on the test tool

[unicoderbot]

Summary

Adds support for the show_uncovered flag to the MCP test tool's input schema. This allows agents to request uncovered line information when a coverage shortfall occurs, rather than being limited to just the coverage percentage.

Changes

• Added show_uncovered boolean parameter to the test tool's MCP schema
• Updated _parseTest to append --show-uncovered flag when the parameter is set to true
• Updated test fixtures to verify the flag is properly passed through to the CLI

Motivation

When the MCP test tool encounters a min_coverage failure, it previously only reported the coverage percentage. The underlying CLI already knows which lines are uncovered via the --show-uncovered flag, but the MCP surface didn't expose this capability. This gap required workarounds like config file settings, which are fragile and require opt-in from every consuming repository.

Closes #1705

[unicoderbot]

CI failed on this PR. I'm looking into it and will push a fix (attempt 1 of 3).

• Preparing environment
  • Cloning repository
  • Setting up dev environment
• Inspecting CI failures
• Working on fix
• Pushing fix

I've pushed a fix for the failing CI, but the coding agent reported the work is incomplete: fixed the formatting build failure; the flame_game e2e failure is unrelated to this PR's MCP changes and needs separate investigation.

Review the new commit and re-run CI before merging.