Make memory graph cluster colors configurable

[advaitpaliwal]

Summary

• add clusterColors to the memory graph theme contract
• read cluster palettes from --graph-cluster-colors or colors.clusterColors
• use the configured palette for node cluster assignment and legend swatches

Why

Consumers can already override most graph colors through CSS variables or the colors prop, but cluster colors were still hard-coded in graph data and legend rendering. This lets host apps fully align the graph palette without patching package internals.

Validation

• bunx biome check packages/memory-graph/src/types.ts packages/memory-graph/src/constants.ts packages/memory-graph/src/hooks/use-graph-theme.ts packages/memory-graph/src/hooks/use-graph-data.ts packages/memory-graph/src/components/legend.tsx
• bun run check-types in packages/memory-graph
• bun run test in packages/memory-graph (172 passed)

[graphite-app]

Inconsistent fallback behavior when clusterColors is empty. The legend shows [colors.memStrokeDefault] (single color), but the graph data functions in use-graph-data.ts fall back to DEFAULT_CLUSTER_COLORS (full palette). This causes a mismatch where the legend could display one color while the actual graph uses the default multi-color palette.

// Fix: Use consistent fallback
const swatches =
	colors.clusterColors.length > 0
		? colors.clusterColors.slice(0, 5)
		: DEFAULT_CLUSTER_COLORS.slice(0, 5)

This ensures the legend accurately represents the colors actually used in the graph when clusterColors is explicitly set to an empty array via overrides.

Suggested change

	const swatches =
	colors.clusterColors.length > 0
	? colors.clusterColors.slice(0, 5)
	: [colors.memStrokeDefault]
	const swatches =
	colors.clusterColors.length > 0
	? colors.clusterColors.slice(0, 5)
	: DEFAULT_CLUSTER_COLORS.slice(0, 5)

Spotted by Graphite



Is this helpful? React 👍 or 👎 to let us know.