Meta: Build system now supports Clang 19

[isif00]

This PR improves the find_compiler.sh script to ensure reliable detection of Clang 19 and future releases #25123 .

Key Changes:

• Rewrote find_newest_compiler() to dynamically scan $PATH for binaries matching <compiler>-<version> (e.g., clang-19).
• Automatically selects the compiler with the supported and highest major version number.

[BuggieBot]

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