Elixir v1.20.0-rc.2 released

Elixir v1.20.0-rc.2 release candidate introduces significant compiler improvements: ~10% faster compilation, a new interpreted mode (up to 5x faster, scales with CPU cores), and cross-clause type inference that catches more bugs and dead code. Struct definition changes now trigger fewer recompilations. New additions include Integer.popcount/1, List.first!/1, List.last!/1, and a Software Bill of Materials guide. A potential breaking change makes map.foo() and mod.foo (without parens) raise errors instead of runtime warnings. Mix gains parallelized dep lock status checks and the interpreted module definition option.