v0.6.1

v0.6.1: Rewrite diagnostics with process monitoring

Replace legacy tests (3-9) that used kernel32 directly (bypassed bundled
DLL) with focused tests that:
- Monitor process tree to see if OpenConsole.exe or conhost.exe spawns
- All ConPTY tests go through ConPtyProcess.spawn() (uses bundled DLL)
- Verify DLL export resolution and file layout in _MEIPASS
- Report which console host the bundled conpty.dll actually launched

This will tell us definitively whether the bundled DLL is working or
silently falling back to system conhost.exe.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>