[Feature] Upgrade TypeScript compiler to 7.0.2

[ConnorQi01]

Summary

Upgrade the project build compiler to TypeScript 7.0.2 while retaining the official TypeScript 6 compatibility package for ESLint and tooling that still depends on the legacy compiler JavaScript API.

Scope

• Use TypeScript 7.0.2 for project compilation.
• Keep the official TypeScript 6 compatibility package available for ESLint and legacy tooling.
• Remove @typescript/native-preview and TypeScript tooling that is no longer used by the build.
• Update the gulp and webpack compilation paths to invoke the TypeScript 7 CLI.
• Preserve preprocessing, localization, source map, and webpack bundle behavior.
• Fix source compatibility issues exposed by TypeScript 7.

Out of scope

• Unrelated production-code refactors or behavioral changes.
• Disabling ESLint or other validation to work around TypeScript 7 compatibility.

Validation

• npm ci
• npm run build
• npx gulp webpack-bundle
• npm test
• npx gulp
• npm run smoke-build
• Verify localization artifacts and source maps remain valid.
• Verify the packaged extension bundle activates successfully.