Avoid repeated dynamic-option classification arrays

[OskarEichler]

Summary

Compute dynamic option names once per runtime-options rebuild and use direct short-circuit Proc/Symbol/Uber::Callable checks. Classification order is preserved.

Reproduction

require 'representable/json/hash'
1000.times { Representable::Definition.new(:name, getter: ->(*) { 1 }, default: 7, as: :alias) }
# Measure elapsed time and GC.stat(:total_allocated_objects) around this bounded loop.

Verification

• Existing master suite on this isolated branch: 545 tests / 701 assertions, zero failures/errors, three existing skips on Ruby 3.2.11. Ruby 4.0.6 retains the same eight legacy inspection-format failures, zero errors and three skips. Existing tests/expectations are unchanged.
• 308 focused checks on Ruby 3.2.11/4.0.6 for this change. XML first-render uses a separate fresh-process check.
• Combined release-based verification with other focused fixes and attributed Use Setter in OverwriteOnNil if a :setter is defined #177/Hash value of null breaks parsing #264/Update MultiJSON usage to address deprecations #273 source backports: 544 tests / 700 assertions pass on Ruby 3.2.11, plus 4,410 focused checks and 36 boundary checks. Package retains 104 paths and unchanged compared metadata. All 36 runtime files compile on both Rubies; no newly introduced default Lint offenses.

Isolated YJIT measurement: three alternating baseline/fixed process pairs, each with five batches of 3,000 definition builds. Median time 0.012017→0.009716s; allocations 234,000→171,000. Bounded local evidence, not production throughput.

Breaking changes / limitations

No documented API change intended. A custom dynamic_options override supplies the same list, now evaluated once per rebuild instead of once per field.

No new/modified checked-in tests. Ruby 2.4–3.1, JRuby, Windows and Linux were not executed locally. Ruby >=2.4 and runtime dependency ranges remain unchanged. External test tooling supplies a legacy MiniTest alias and ruby-prof 1.7.x; no assertions were changed. No production verification is claimed.