Function buildIntelligenceMindmapSection

buildIntelligenceMindmapSection(
    imap: IntelligenceMindmap | null | undefined,
    lang?: string,
    heading?: string,
): string
Generate a multi-layer intelligence mindmap section as an HTML string.

Renders a hierarchical policy domain intelligence map with:
- Influence-weighted nodes (CSS --node-influence custom property)
- Actor-network visualization via <details> child overlays
- Policy connection indicators in a collapsible <details> panel
- Stakeholder perspective overlays via <details>/<summary> (no JS)
- WCAG 2.1 AA accessible roles, labels, and meter elements
Returns an empty string when imap is null/undefined or has no layers with nodes.
Parameters
- imap: IntelligenceMindmap | null | undefined
  Intelligence mindmap data.
- lang: string = 'en'
  BCP 47 language code for section headings.
- Optionalheading: string
  Optional heading override.
Returns string
HTML string for the intelligence mindmap section, or empty string.
- Defined in src/generators/mindmap-content.ts:553