Styler-ify Credo rules: FilterFilter, RejectReject, ExpensiveEmptyEnumCheck, and RaiseInsideRescue

[JesseHerrick]

• Refactor.FilterFilter: Enum.filter |> Enum.filter => single filter combined with &&
• Refactor.RejectReject: Enum.reject |> Enum.reject => single reject combined with ||
• Warning.ExpensiveEmptyEnumCheck: length(x) == 0 => x == []; Enum.count(x) == 0 => Enum.empty?(x)
• Warning.RaiseInsideRescue: raise foo inside a rescue clause => reraise foo, __STACKTRACE__

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Note

Medium Risk
Adds new AST rewrite rules that change emitted code for common patterns (pipes, empty checks, rescue re-raises) and adjusts directive alias-lifting behavior, which could affect formatting/output in edge cases.

Overview
Styler now enforces four additional Credo rules by rewriting code: it merges chained Enum.filter/2 and Enum.reject/2 pipes into a single call with a combined predicate, replaces expensive emptiness checks like length(x) == 0/Enum.count(x) == 0 with x == [] or Enum.empty?/1, and rewrites raise inside rescue clauses to reraise ..., __STACKTRACE__ to preserve stacktraces.

It also changes alias-lifting so require directives are no longer rewritten via aliases (avoiding invalid ordering where require Bar would appear before alias Foo.Bar), updates documentation to recommend disabling the newly covered Credo checks, and adds targeted tests for all new rewrite behaviors.

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