Add baseline anti-cheat guards

[rafael81]

/claim #2
/claim #4

Summary

• keep AntiCheat.cpp buildable and preserve the Windows debugger, suspicious-process, and optional CRC32 executable integrity checks
• add the missing Python monitor with debugger detection, Windows process scanning, and optional JAVELIN_EXPECTED_SHA256 script integrity checks
• document C++/Python run steps and expected integrity hash setup
• add regression tests for process detection, guarded exits, and Python script integrity behavior
• include short visual demo assets in the README

Demo

• Demo video: https://raw.githubusercontent.com/rafael81/py-workedtask/feat/basic-anti-cheat-issue-2/docs/anti-cheat-demo.mp4
• Animated GIF fallback: https://raw.githubusercontent.com/rafael81/py-workedtask/feat/basic-anti-cheat-issue-2/docs/anti-cheat-demo.gif

Validation

$ python3 -m unittest discover -s tests
............
----------------------------------------------------------------------
Ran 12 tests in 0.002s

OK

$ c++ -std=c++17 -Wall -Wextra -pedantic AntiCheat.cpp -o /tmp/javelin-anticheat-check

$ /tmp/javelin-anticheat-check
[Javelin AntiCheat] Windows-only checks skipped on this platform.

$ git diff --check

Windows-specific process and debugger APIs are implemented behind _WIN32; the local compile check verifies the non-Windows CI-safe path from this environment.

This PR was prepared with AI assistance and manually reviewed before submission.

[rafael81]

Follow-up update: I added a short MP4 demo asset alongside the existing GIF so the PR directly satisfies the Algora demo-video guideline.

New asset:

• https://raw.githubusercontent.com/rafael81/py-workedtask/feat/basic-anti-cheat-issue-2/docs/anti-cheat-demo.mp4

Re-ran validation after the update:

• python3 -m unittest discover -s tests
• c++ -std=c++17 -Wall -Wextra -pedantic AntiCheat.cpp -o /tmp/javelin-anticheat-check && /tmp/javelin-anticheat-check
• git diff --check

This remains AI-assisted and manually reviewed.

[rafael81]

Follow-up hardening commit pushed: 64b5a74.

This keeps the existing behavior but makes the Python Windows process scan more robust by:

• splitting tasklist CSV parsing into a tested helper,
• returning an empty process list if tasklist is unavailable or fails, so the monitor does not crash during startup,
• adding regression coverage for CSV parsing and scan failure handling.

Re-ran validation after the update:

• python3 -m unittest discover -s tests
• c++ -std=c++17 -Wall -Wextra -pedantic AntiCheat.cpp -o /tmp/javelin-anticheat-check && /tmp/javelin-anticheat-check
• git diff --check

This follow-up was AI-assisted and manually reviewed.

[rafael81]

Follow-up integrity commit pushed: 75424f5.

This completes the Python side of #4 while keeping the original #2 scope intact:

• adds optional JAVELIN_EXPECTED_SHA256 script integrity verification,
• exits with the guarded integrity code on missing/malformed/mismatched configured hashes,
• documents the expected-hash setup flow,
• adds regression coverage for no-env, matching hash, mismatch, and integrity-driven guarded exits.

Re-ran validation after the update:

• python3 -m unittest discover -s tests -> 12 tests passed
• c++ -std=c++17 -Wall -Wextra -pedantic AntiCheat.cpp -o /tmp/javelin-anticheat-check
• /tmp/javelin-anticheat-check
• git diff --check

The PR body now includes /claim #4 in addition to /claim #2. This follow-up was AI-assisted and manually reviewed.

[rafael81]

@algora-pbc /claim #4

[rafael81]

@algora-pbc /claim #2