[Feature] Add Integrity Verification (Hash of Executable/Script)

[giteku]

Title: [Feature] Add Integrity Verification (Hash of Executable/Script)
Description:
Implement optional integrity checks for both implementations to detect tampering:

• C++: compute CRC32 or SHA-256 of the running executable and compare to a build-time constant.
• Python: compute SHA-256 of the script file and compare to an env var (JAVELIN_EXPECTED_SHA256).
  Acceptance Criteria:
• Non-matching hash results in guarded exit.
• Document how to set the expected values.

fixes feat 🎫 #3

[orangecurl]

/bounty $50

[algora-pbc]

💎 $100 bounty • Toms DeVoss

Steps to solve:

1. Start working: Comment /attempt #4 with your implementation plan
2. Submit work: Create a pull request including /claim #4 in the PR body to claim the bounty
3. Receive payment: 100% of the bounty is received 2-5 days post-reward. Make sure you are eligible for payouts

❗ Important guidelines:

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Thank you for contributing to javelin-anticheat/py-workedtask!

[dawgrg]

/attempt #4

[dawgrg]

/tip 100

[MAVRICK-1]

/attempt #4

[Brijeshthummar02]

/attempt #4