Fix Sorbet LSP crash from two config dirs - #23980

The Sorbet "Brew Typecheck" extension in VS Code wouldn't start: it kept crashing and looping on launch, with Sorbet's language server requires a single input directory. However, 2 are configured: [., ../../.github/scripts] followed by Pending response rejected since connection got disposed.

The cause: sorbet/config gained a second --dir for .github/scripts in 729e835 (#23915), but that file's arguments apply to every srb tc invocation including --lsp, which only supports one input directory. This moves .github/scripts out of the shared config and adds it on the command line instead, everywhere except --lsp runs.

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Disclosure: drafted with Claude Code assistance; I reviewed the change and reasoning and will answer questions myself.