Add a new "Constellation" memory visualization as the default view in the
control plane, powered by @chenglou/pretext for DOM-free text layout on canvas.
- Canvas-rendered zoomable/pannable memory map with spatial label deconfliction
- Nodes colored by link-count heat gradient (Hindsight brand teal→cyan→blue)
- Star-like rendering with varied size/opacity based on connectivity
- Hover shows rich tooltip with full memory metadata (text, entities, tags, dates)
- Hover highlights connected nodes and their links, dims the rest
- Click to select and view memory details in the side panel
- Fullscreen mode toggle
- Link type legend and heat gradient legend on the HUD
Also optimizes the graph API endpoint:
- Entity query now filters by visible unit IDs (was doing full table scan)
- Links query caps at 10k edges sorted by weight (was returning 500k+ uncapped)
- Replaced expensive DISTINCT ON with LEAST/GREATEST sort with simple ORDER BY
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