fix: mark blocked invokes as unexecuted

[Wany-i]

Summary

• make every blocked invoke response explicitly return
  esponse.data.executed=false\
• cover all five fail-closed branches and MCP structured output
• bump the package and MCP server version to 1.0.1

Verification

• 13 pytest tests passed
• wheel and sdist built successfully
• independent TG02 release-gate batch review passed the commit/PR/CI gate

Safety

• no command execution behavior was added
• blocked and completed invoke responses both remain side-effect free
• WorkBuddy production installation remains gated until the v1.0.1 release artifact is verified