Implements DebugAgent class (Task 2) with launch, set/remove breakpoint,
get_registers, read/write_memory, continue_execution, and get_status.
Handles WOW64 WX86 exception codes (0x4000001F/0x4000001E), keeps debuggee
suspended via _pending_event until caller resumes, and tracks stopped thread
for correct register reads. Smoke-tested against live HAVOC_NOCD.EXE: stopped
at breakpoint@0x40C8E0 with eip=0x40c8e0 confirmed.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TN4Ytn3gdWRonNmHpisWQv
