Add pre-commit hook installation to onboarding and upgrade processes

- prompts/onboarding.md: Step 2c installs git pre-commit hook for new projects
- scripts/upgrade.sh: Installs pre-commit hook during upgrade (with symlink detection)
- scripts/install.sh: Mentions hook installation in post-install next steps

scripts/install.sh

@@ -59,4 +59,10 @@ fi
 
 echo ""
 echo "Installation complete."
-echo "Next step: cd into a project and run the onboarding prompt."
+echo ""
+echo "Next steps:"
+echo "  1. cd into a project and run the onboarding prompt"
+echo "  2. In each project that uses git, install the pre-commit hook:"
+echo "     ln -sf ~/.automaton/scripts/git-hooks/pre-commit .git/hooks/pre-commit"
+echo ""
+echo "This hook blocks commits when no task is in an edit-allowed phase."

scripts/upgrade.sh

@@ -54,4 +54,32 @@ fi
 echo ""
 echo "=== Upgrade Complete ==="
 echo "Run 'python ~/.automaton/scripts/status.py --list --project $PROJECT_DIR' to verify task states."
-echo "Run 'python ~/.automaton/scripts/status.py --audit --project $PROJECT_DIR' to check for violations."
+echo "Run 'python ~/.automaton/scripts/status.py --audit --project $PROJECT_DIR' to check for violations."
+echo ""
+
+# Install pre-commit hook if project uses git
+GIT_DIR="$PROJECT_DIR/.git"
+if [ -d "$GIT_DIR/hooks" ]; then
+    HOOK_TARGET="$GIT_DIR/hooks/pre-commit"
+    HOOK_SOURCE="$FRAMEWORK_DIR/scripts/git-hooks/pre-commit"
+    if [ -f "$HOOK_TARGET" ]; then
+        if [ -L "$HOOK_TARGET" ]; then
+            EXISTING_TARGET="$(readlink "$HOOK_TARGET")"
+            if [ "$EXISTING_TARGET" = "$HOOK_SOURCE" ]; then
+                echo "Pre-commit hook already linked to automaton."
+            else
+                echo "WARNING: pre-commit hook already exists (symlink to: $EXISTING_TARGET)"
+                echo "  To use automaton's hook, run: ln -sf $HOOK_SOURCE $HOOK_TARGET"
+            fi
+        else
+            echo "WARNING: pre-commit hook already exists at $HOOK_TARGET"
+            echo "  To replace it with automaton's hook, run: ln -sf $HOOK_SOURCE $HOOK_TARGET"
+        fi
+    else
+        ln -sf "$HOOK_SOURCE" "$HOOK_TARGET"
+        echo "Installed pre-commit hook at $HOOK_TARGET"
+    fi
+else
+    echo "NOTE: No .git/hooks/ directory found. Install the hook manually if this project uses git:"
+    echo "  ln -sf $FRAMEWORK_DIR/scripts/git-hooks/pre-commit \$PROJECT_DIR/.git/hooks/pre-commit"
+fi