Build prototype hex crawl backend and frontend

[wvaske]

Summary

• implement the Phoenix backend with Absinthe GraphQL schema, Phoenix Channels, Oban worker stub, and in-memory state seeded with a demo campaign
• scaffold the SvelteKit frontend that renders DM and player map views with MapLibre tiles, GraphQL data fetching, and websocket updates via Phoenix channels
• add docker-compose orchestration, Dockerfiles, and updated documentation covering setup requirements and known limitations

Testing

• mix format
• mix deps.get (fails: 403 Forbidden from hex.pm in restricted environment)
• npm install --package-lock-only (fails: 403 Forbidden from npm registry in restricted environment)

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[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Map view never updates after initial render

The reactive block that refreshes the MapLibre sources only references map, so it executes exactly once when the map instance is created and never again. Subsequent updates to mapDetail—for example when the DM reveals hexes, moves players, or switches to another map—do not trigger updateSources (or re-run fitBounds), leaving the displayed map permanently stale. Consider making the reactive block depend on mapDetail as well (e.g. $: if (map && mapDetail) { updateSources(); fitBounds(); }) so realtime or navigation changes propagate to the rendered layers.

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