perf(router): sort handlers by score only when necessary

[EdamAme-x]

Sorting was also done when number of handlers was 0 or 1, so it is no longer done.
Also, there is no need to create a new variable.

Benchmarks

In Node

summary for all together
  Hono RegExpRouter
   1.39x faster than Memoirist
   1.5x faster than koa-tree-router
   1.66x faster than @medley/router
   2.15x faster than rou3
   2.33x faster than trek-router
   2.97x faster than find-my-way
   4.28x faster than Hono PatternRouter
   5.43x faster than radix3
   8.01x faster than koa-router
   8.96x faster than Hono TrieRouter
   9.13x faster than Hono BeforeTrieRouter
   39.24x faster than express (WARNING: includes handling)

In Bun

summary for all together
  Hono RegExpRouter
   1.01x faster than Memoirist
   1.23x faster than @medley/router
   2.12x faster than koa-tree-router
   2.13x faster than rou3
   2.19x faster than radix3
   2.33x faster than find-my-way
   3.87x faster than trek-router
   4.06x faster than Hono PatternRouter
   5.43x faster than koa-router
   10.29x faster than Hono TrieRouter
   10.45x faster than Hono BeforeTrieRouter
   11.37x faster than express (WARNING: includes handling)

There is some improvement in performance, though not significantly.

The author should do the following, if applicable

• Add tests
• Run tests
• bun run format:fix && bun run lint:fix to format the code
• Add TSDoc/JSDoc to document the code

[codecov]

Codecov Report

Attention: Patch coverage is 85.71429% with 1 line in your changes missing coverage. Please review.

Project coverage is 91.69%. Comparing base (44a50bd) to head (8abc420).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
src/router/trie-router/node.ts	85.71%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3697      +/-   ##
==========================================
- Coverage   91.70%   91.69%   -0.01%     
==========================================
  Files         159      159              
  Lines       10145    10148       +3     
  Branches     2879     2873       -6     
==========================================
+ Hits         9303     9305       +2     
- Misses        840      841       +1     
  Partials        2        2              

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[yusukebe]

LGTM!

[yusukebe]

@EdamAme-x

Thanks! I'll merge it.