Summary

• Adds @warpgrid/bun-sdk/preload module — a Bun preload script that configures WarpGrid for native development mode
• Sets WARPGRID_MODE=development env var and initializes globalThis.warpgrid namespace with { mode: "development" }
• Ensures __WARPGRID_WASM__ is NOT set so detectMode() returns "native" in Bun environments
• Adds "./preload" export to package.json for bun run --preload @warpgrid/bun-sdk/preload and bunfig.toml usage

Test plan

• 9 new tests in tests/preload.test.ts covering:
  • Environment variable setup (WARPGRID_MODE=development)
  • globalThis.warpgrid initialization and shape
  • Native mode detection (__WARPGRID_WASM__ not set)
  • Idempotency (double-import safety)
  • Existing property preservation
  • Handler integration with detectMode()
  • Module-load simulation (bun run --preload)
• All 195 tests pass (9 new + 186 existing)
• TypeScript typecheck passes

Resolves #80

🤖 Generated with Claude Code