Test suite rewrite and dependency updates

[mikkelam]

Completely rewrote the test suite since the old one was just commented out static plugin code that didn't test anything useful.

Changes:

• Updated @elysiajs/eden from 1.2.0 to 1.3.0
• Removed broken index.test.ts with commented static plugin tests
• Added comprehensive test coverage:
  • core.test.ts - Core OpenTelemetry functionality
  • integration.test.ts - Elysia framework integration
  • advanced.test.ts - Advanced tracing features
  • test-setup.ts - Shared test utilities, loaded with bun --preload

Test improvements:

• 31 tests covering OpenTelemetry behavior
• Proper span lifecycle testing with capture utilities
• HTTP method tracing, middleware integration, nested spans
• Error handling, concurrent requests, trace propagation
• Real integration tests using eden treaty client

Unrelated
If the author is happy with this PR, i would love to improve the otel package to also handle logging