Fix same-branch matching

[CathalMullan]

Solve it stupidly first, then worry about performance.
We might need to introduce a 3rd state to quick_dynamic?

EDIT: No, solution is quite simple actually. Shouldn't impact performance that much. Won't appear on benchmarks, since none of our benchmarks measure inline search speed.

Let's add more tests too.

[codspeed-hq]

CodSpeed Performance Report

Merging #149 will not alter performance

_{Comparing 148-router-fails-to-route-to-more-specific-options (517c1ee) with main (0a3ceb0)}

Summary

✅ 16 untouched benchmarks

[codecov]

Codecov Report

Attention: Patch coverage is 87.87879% with 4 lines in your changes missing coverage. Please review.

✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
src/node/search.rs	87.87%	1 Missing and 3 partials ⚠️

Files with missing lines	Coverage Δ
src/node/search.rs	78.71% <87.87%> (+0.60%)	⬆️