feat!: change frequency type and remove evidence-requirements

[jpower432]

Description

This PR alters Policy Assessment Plans. Details below.

Schema Changes

Schema Changes Made

• No schema changes
• Audit Log schema (auditlog.cue) changes
• Capability Catalog schema (capabilitycatalog.cue) changes
• Control Catalog schema (controlcatalog.cue) changes
• Enforcement Log schema (enforcementlog.cue) changes
• Evaluation Log schema (evaluationlog.cue) changes
• Guidance Catalog schema (guidancecatalog.cue) changes
• Mapping Document schema (mappingdocument.cue) changes
• Policy Document schema (policy.cue) changes
• Principle Catalog schema (principlecatalog.cue) changes
• Risk Catalog schema (riskcatalog.cue) changes
• Threat Catalog schema (threatcatalog.cue) changes
• Vector Catalog schema (vectorcatalog.cue) changes
• Other

Schema Change Details

⚠️ Breaking changes to experimental schema ONLY

frequency field in #AssessmentPlan now int (days) instead of string. evidence-requirements field removed; replaced with evidence-types array of #EvidenceTypeDefinition entries defining valid evidence types and their validity periods.

Consumers must update:

• Parse frequency as integer days, not string
• Use evidence-types array instead of evidence-requirements string
• No automatic migration path; requires manual assessment plan updates

Testing

• Unit tests added/updated
• Manual testing performed
• Test data updated (if applicable)

Related Issues

Related to #417

Reviewer Hints

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