feat: add replace subcommand with multi-pattern support

scripts/smoke-test-replace.sh

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+BIN="go run"
+TMP_DIR="$(mktemp -d)"
+trap 'rm -rf "$TMP_DIR"' EXIT
+
+mkdir -p "$TMP_DIR/nested"
+touch "$TMP_DIR/foo_draft.txt"
+touch "$TMP_DIR/nested/bar_draft.txt"
+
+echo "Previewing replacements..."
+$BIN "$ROOT_DIR/main.go" replace draft Draft final --path "$TMP_DIR" --recursive --dry-run >/dev/null
+
+echo "Applying replacements..."
+$BIN "$ROOT_DIR/main.go" replace draft Draft final --path "$TMP_DIR" --recursive --yes >/dev/null
+
+if [[ ! -f "$TMP_DIR/foo_final.txt" ]]; then
+  echo "expected foo_final.txt to exist" >&2
+  exit 1
+fi
+
+if [[ ! -f "$TMP_DIR/nested/bar_final.txt" ]]; then
+  echo "expected bar_final.txt to exist" >&2
+  exit 1
+fi
+
+echo "Undoing replacements..."
+$BIN "$ROOT_DIR/main.go" undo --path "$TMP_DIR" >/dev/null
+
+if [[ ! -f "$TMP_DIR/foo_draft.txt" ]]; then
+  echo "undo failed to restore foo_draft.txt" >&2
+  exit 1
+fi
+
+if [[ ! -f "$TMP_DIR/nested/bar_draft.txt" ]]; then
+  echo "undo failed to restore nested/bar_draft.txt" >&2
+  exit 1
+fi
+
+echo "Smoke test succeeded."