---
id: TASK-146
title: Sankey Power Overlay — dual-bar node sizing
status: To Do
assignee: []
created_date: '2026-04-16 18:56'
labels:
  - rnetwork
  - governance
  - power-indices
dependencies:
  - TASK-144
references:
  - modules/rnetwork/components/folk-trust-sankey.ts
  - src/encryptid/power-indices.ts
priority: medium
---

## Description

<!-- SECTION:DESCRIPTION:BEGIN -->
Add power index overlay to `folk-trust-sankey.ts` right-column nodes.

## What
Right-column delegate nodes currently show rank badge + received weight %. Add a second bar showing Banzhaf power %, creating a visual comparison: raw weight vs actual coalitional power.

## Primitive
- Fetch power indices once on authority change: `GET /rnetwork/api/power-indices?space={space}&authority={authority}`
- Build `Map<did, { banzhaf, shapleyShubik }>` lookup
- Right-column nodes get dual horizontal bars:
  - Top bar (gray): raw received weight %
  - Bottom bar (authority color): Banzhaf power %
- Nodes where power >> weight glow red (disproportionate influence)

## Implementation
- `folk-trust-sankey.ts`: Add `powerMap` field, fetch in `loadData()`
- Modify `renderRightNodes()` to draw second bar below weight bar
- Add CSS for `.power-bar` with transition animation
- ~60 lines, one fetch, zero new files
<!-- SECTION:DESCRIPTION:END -->

## Acceptance Criteria
<!-- AC:BEGIN -->
- [ ] #1 Dual bars on right-column nodes: weight % and Banzhaf %
- [ ] #2 Red glow on nodes where Banzhaf > 1.5x weight share
- [ ] #3 Bars animate on authority tab switch
- [ ] #4 Toggle to show/hide power overlay
<!-- AC:END -->