Ensure Redis has stage 2 solutions and hints for all languages

[TropicolX]

[!NOTE] Implements TCP servers that reply with “+PONG\r\n” on connection for all language tracks, adding necessary build/run scaffolding and language-specific hints.

• Stage 2 Implementations:
  • Return "+PONG\r\n" on first client connection across: C, C++, Clojure, Crystal, C#, Elixir, Gleam, Haskell, Java, JavaScript, Kotlin, OCaml, Odin, PHP, Ruby, Scala, Swift, TypeScript, Zig.
• Build/Run Scaffolding:
  • Add per-language compile/run scripts and project configs (e.g., cmake, stack, sbt, gradle, dune, swift-nio package, zig build, etc.).
• Guidance & Docs:
  • Add config.yml hints per language (how to accept connections and send responses).
  • Add language-specific README.md with stage instructions.

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