docs(mapgen-studio): mark X6 and X7 as executed with hex-convention audit and world-console map-params revision notes

[mateicanavra]

Adds documentation for two follow-up slices (X6 and X7) that landed after the initial redesign gates passed.

X6 – Tile Game Geometry
Documents the hex-convention audit finding that Civ7's plot grid is pointy-top odd-R and that mapgen-core's odd-Q labeling is a mislabel producing an irregular tiling, which was the root cause of the vertically squished grid. Both tile spaces now render regular pointy-top odd-R hexes on a shared world frame, and TILE_BORDER_COLOR is unified to a single graphite ink value (#0d0d11 α200) across both themes. The engine-side odd-Q→odd-R migration is tracked separately as out of studio scope.

X7 – World Console Map Params
Documents the revised scoping decision for the Resources footer UI. The Resources select, label, and History-tooltip line remain in the World console under the zone boundary rule, since the map pipeline reads it. Players is retained because playerCount feeds PlayersLandmass1/2. All backend resources plumbing — WorldSettings.resources, persistence, fingerprints, run requests, proof identity, and the worker's StudioResourcesMode write — is left byte-identical, with the wire reserved for the placement stack's resources vertical. No reader was found on any branch before the UI was touched.

[github-actions]

Railway preview (MapGen Studio): not provisioned for this PR.

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Debug: {"isClosed":false,"isFork":false,"suppress":false,"force":false,"isTopOfStack":false,"hasToken":true,"draft":false}

[mateicanavra]

Merge activity

• Jun 12, 8:50 PM UTC: A user started a stack merge that includes this pull request via Graphite.
• Jun 12, 10:12 PM UTC: Graphite rebased this pull request as part of a merge.
• Jun 12, 10:12 PM UTC: @mateicanavra merged this pull request with Graphite.