feat(maps): draw remaining exploration and terrain inside native maps

[Mat4m0]

What changed

Compass terrain and range rings, Mission Map artwork, and World Map exploration markers now draw inside their native map owners. Native movement and clipping position them, and later game panels and tooltips cover them.

Explored areas stay clear. Remaining exploration keeps the existing marker styles; large cached tiles use bounded clusters instead of losing all markers. Walkable terrain retains its darker outside veil.

Why

Positioned browser drawing surfaces could cover native UI and repeatedly repaint during movement. The native layers reuse textures and meshes, cache map artwork through small pans, quantize raster detail during zoom, and isolate hover updates. The old browser drawing paths are removed.

Invariant

Exact native guards authorize the derived rendering code. Missing support hides only the affected surface. Texture bounds, epoch checks, unsigned wasm32 upload addresses, rollback, and cleanup have executable tests. Saved map styles remain compatible.

Delivery

Targets the test-containment layer and ultimately main. Recommend one Beta train for the completed native-rendering stack. This changes native rendering and requires gameplay QA on the exact signed candidate before release.

Verification

The maps-only layer passes pnpm check. Actual-client WASM fixtures cover native map/Compass ownership and malformed uploads. Focused tests cover caching, large-map fallback, independent availability, cleanup failures, and allocations above 2 GiB. Electron map controls pass at normal size and 200% zoom. The combined stack passes integration, release checks, packaging, and packaged smoke tests.

Matthias accepted the preceding development build's map motion and native UI coverage. That observation does not certify the later signed release. No FPS improvement is claimed from offline tests.

• I kept this pull request focused.
• I ran the relevant checks.
• I did not add game binaries, credentials, diagnostics, or private traffic.
• I updated documentation when behavior or an invariant changed.