Mirror the JavaScript layout from PR #21953:
- Move SystemPromptInjection.ql / UserPromptInjection.ql to src/Security/CWE-1427
- Move customizations, query and framework libs to python/ql/lib
- Move the AIPrompt concept to the production Concepts.qll
- Drop the experimental tag; py/system-prompt-injection (high precision) now
joins the code-scanning, security-extended and security-and-quality suites,
while py/user-prompt-injection (low precision) stays out of the default suites
- Move query tests to python/ql/test/query-tests/Security
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
