What

packages/core/package.json declared both viewport-mercator-project and @types/viewport-mercator-project as direct deps, but packages/core/src never actually imports the package — the only mention is a documentation URL comment in CoordinateSystemService.ts:124, which is not a code usage.

This PR removes the redundant declarations from core.

The real runtime consumer is packages/maps/src/lib/web-mercator-viewport.ts (value import WebMercatorViewport from 'viewport-mercator-project', exercised by all 8 map adapters). packages/maps/src/earth/Viewport.ts uses an import type for an interface-only field that is never instantiated and whose projectFlat is never called from earth/map.ts — also covered by the maps-scope declaration, not core's.

The maps package therefore retains its own declaration and the workspace dependency graph is essentially unchanged — pnpm-lock.yaml only drops the importer-of-record lines for core (-6 lines).

Why now (modernization investigation)

A prior turn looked into modernizing viewport-mercator-project to the latest npm tag. Findings:

• The npm-latest tag (7.0.4) is deprecated by vis.gl and is literally module.exports = require('@math.gl/web-mercator') under the hood.
• The underlying @math.gl/web-mercator@4.1.0 uses a different projection convention — no 2^zoom scaling on projectFlat / center, and substantially different matrix conventions.
• Runtime comparison at the same {width,height,longitude,latitude,zoom,pitch,bearing} options showed a 2^zoom factor divergence in projectFlat / center, which would break L7's rendering pipeline downstream (layers / shaders / CameraService).
• v6.2.3 itself is not deprecated — only the npm-latest wrapper is. So staying on v6.2.3 is fine.

A full migration to the latest is therefore out of scope for this PR. The only uncontroversially-safe cleanup is removing core's dead direct declaration — which is what this commit does.

A future "vendor v6 source into the repo" PR (preserve v6 behavior exactly, remove the external dep completely) is feasible but requires its own risk review and visual regression pass, and is not in scope here.

Changes

• packages/core/package.json — removed viewport-mercator-project (^6.2.1) from dependencies, @types/viewport-mercator-project (^6.1.0) from devDependencies.
• pnpm-lock.yaml — drops 6 lines (the importer-of-record entry for core; the package itself stays because maps still uses it transitively).

packages/maps/package.json is intentionally untouched — maps is the legitimate consumer.

Validation

• Core tsc --noEmit -p packages/core/tsconfig.json: clean.
• Maps tsc --noEmit -p packages/maps/tsconfig.json: only pre-existing baseline noise (.glsl module resolution + unrelated camera.ts undefined checks); no new errors from this change.
• prettier (CI's check-format.sh glob **/*.{ts,tsx,js,jsx,json,md,css,less}): packages/core/package.json clean. (Lockfile yaml is outside CI's prettier glob.)

Risk

Zero runtime risk — core has no actual code usage of the package. Maps and the rest of the rendering pipeline are untouched.