fix: handle missing types in CustomVulnerability init

[frankentini]

Problem

When CustomVulnerability is initialized without the types parameter (which is Optional[List[str]] and defaults to None), the constructor crashes with an AttributeError because self.types is only set inside the if types: block but is unconditionally accessed in super().__init__(self.types).

# This crashes:
cv = CustomVulnerability(name='Data Leakage', criteria='test')
# AttributeError: 'CustomVulnerability' object has no attribute 'types'

Fix

When types is not provided, default to a single-member enum derived from the vulnerability name. This ensures self.types is always iterable and the vulnerability can be used without explicitly listing types.

Tests

Added test cases for:

• Initialization without types parameter
• get_name() works without types
• Single-type initialization

[vercel]

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[A-Vamshi]

Hey @frankentini, thanks for the PR :)