Enforce CWE on sast_false_positive flows

What does this MR do and why?

Adds the ability to filter AI triage eligibility based on CWE classes.

With the change, we check whether the vulnerability belongs to one of the allowed CWE categories defined in the relevant configuration. If no CWE classes are configured, all vulnerabilities pass through as before. If specific classes are listed, only vulnerabilities matching those categories are eligible for auto flow.

Changelog: added
EE: true

Related issue

[Backend] Introduce a new Eligibility module fo... (#627964 - closed) • Gal Katz

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