Initial import from garrytan/gstack@026751e (main snapshot via local relay)

Source: https://github.com/garrytan/gstack/commit/026751e

scripts/setup-scc.sh

@@ -0,0 +1,71 @@
+#!/usr/bin/env bash
+# setup-scc.sh — install scc (github.com/boyter/scc), used by
+# scripts/garry-output-comparison.ts for logical-line classification of added lines.
+#
+# Why standalone (not a package.json dependency): 95% of gstack users never run
+# the throughput script. Making scc a required install step for every `bun install`
+# would bloat onboarding for no reason. This script is invoked only when you
+# actually want to run garry-output-comparison.ts.
+#
+# Usage: bash scripts/setup-scc.sh
+set -euo pipefail
+
+if command -v scc >/dev/null 2>&1; then
+  echo "scc is already installed: $(command -v scc)"
+  echo "Version: $(scc --version 2>/dev/null || echo 'unknown')"
+  exit 0
+fi
+
+OS="$(uname -s)"
+case "$OS" in
+  Darwin)
+    if command -v brew >/dev/null 2>&1; then
+      echo "Installing scc via Homebrew..."
+      brew install scc
+    else
+      echo "Homebrew not found. Install from https://brew.sh or download scc manually:"
+      echo "  https://github.com/boyter/scc/releases"
+      exit 1
+    fi
+    ;;
+  Linux)
+    if command -v apt-get >/dev/null 2>&1; then
+      echo "Attempting apt-get install scc..."
+      if sudo apt-get install -y scc 2>/dev/null; then
+        echo "Installed via apt."
+      else
+        echo "scc not in apt repos. Download the Linux binary manually:"
+        echo "  https://github.com/boyter/scc/releases"
+        echo "  After download: chmod +x scc && sudo mv scc /usr/local/bin/"
+        exit 1
+      fi
+    elif command -v pacman >/dev/null 2>&1; then
+      echo "Installing scc via pacman..."
+      sudo pacman -S --noconfirm scc
+    else
+      echo "Unknown Linux package manager. Download the binary manually:"
+      echo "  https://github.com/boyter/scc/releases"
+      exit 1
+    fi
+    ;;
+  MINGW*|MSYS*|CYGWIN*)
+    echo "Windows detected. Download the scc Windows binary from:"
+    echo "  https://github.com/boyter/scc/releases"
+    echo "Add it to your PATH."
+    exit 1
+    ;;
+  *)
+    echo "Unknown OS: $OS. Download scc manually:"
+    echo "  https://github.com/boyter/scc/releases"
+    exit 1
+    ;;
+esac
+
+# Verify install
+if command -v scc >/dev/null 2>&1; then
+  echo "scc installed: $(command -v scc)"
+  scc --version
+else
+  echo "Install appears to have failed. scc not found in PATH after install."
+  exit 1
+fi