feat: Update CLAUDE.md files, add coolify skill

legalconsenthub-backend/CLAUDE.md

@@ -97,6 +97,8 @@ formElementSections:
 
 1. **Never add SQL migrations** - They will be handled by the user
 2. **Use mapper classes** - All DTO ↔ Entity conversions must happen in dedicated mapper classes (never in services/controllers)
+   - **CRITICAL: Entity + Mapper must be updated together** — When a new field is added to an OpenAPI DTO, you MUST update BOTH the entity class AND the mapper. A field present in the DTO but absent from the entity will silently return `null` from the API with no compile error. New entity fields that are persisted require a SQL migration (the user handles this).
+   - For JSON-typed fields (e.g. `GroupCondition`), use `@JdbcTypeCode(SqlTypes.JSON)` + `@Column(columnDefinition = "jsonb")`, same as `FormElement.visibilityConditions`.
 3. **PDF Export Validation** - After changes to form elements, visibility, or spawning:
    - Test both HTML and PDF export for real form instances
    - Verify all element types render correctly