Add support r-teleport on detached content.

[koculu]

Summary

This PR improves r-teleport robustness and adds focused coverage around component fallthrough + nested component usage.

What changed

• Simplified teleport target resolution in Binder.ts:
  • Use document.querySelector(...) when available.
  • If document lookup is unavailable at bind time, walk the element parent chain to the root and resolve target there.
• Added integration tests in createComponent.spec.ts:
  • :r-teleport fallthrough from component host to component root.
  • Nested component teleport when parent host binds :r-teleport.
  • Nested component teleport when parent binds :r-teleport on <ChildComp ...>.
• Added edge test in binder-edge.spec.ts:
  • Verifies detached teleport path falls back to parent-chain root when document lookup is unavailable.
• Version bump in package.json: 1.3.9 -> 1.4.0.