Use .public_send instead of .send for calls to public methods

[AbishekRaj2007]

While going through the codebase for calls that use .send to invoke a method by a dynamic name, I found a batch of spots where the method being called is actually public .send was being used just to look up a method whose name isn't known until runtime (e.g. Tty.send(color), formula.send(spec_name)), not because anything private needed to be reached.

Since .send bypasses Ruby's private visibility check entirely, using it on public methods is a bit misleading to read — it makes a caller look like it might be reaching into internals when it isn't. public_send does the exact same dynamic lookup but only succeeds if the method is actually public, so it documents that intent and behaves identically here since every method involved already was public.

For each of the 20 call sites, I checked the receiver's class definition to confirm the method has no private marker before switching it over, so this should be a no-op behavior-wise.

Left untouched (need private access, so can't switch):

• pour_bottle_check.rb - calls define_method, always private
• api_hashable.rb - calls remove_const, always private
• cli/parser.rb - calls a dynamically-named legacy _args method that may be defined by third-party tap commands; couldn't confirm it's always public, so left as-is to avoid breaking external taps

Note: I have used Claude Sonnet 5 only to change in code and carefully reviewed it before pushing and this PR was raised by myself and no AI is involved in writing the pr.

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• I did not use AI/LLM to create this PR, or I disclosed the tool/model below and reviewed its output; I did not attribute commits to AI and will answer maintainer questions and review comments myself without AI/LLM.

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[MikeMcQuaid]

Looks good so far! Please force-push to trigger CI again after the GitHub incident.