refactor: finish facade migration for precheck and executor

scripts/install_local.sh

@@ -0,0 +1,35 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+APP_HOME="${COINHUNTER_APP_HOME:-$HOME/.local/share/coinhunter-cli}"
+VENV_DIR="$APP_HOME/venv"
+BIN_DIR="${COINHUNTER_BIN_DIR:-$HOME/.local/bin}"
+LAUNCHER="$BIN_DIR/coinhunter"
+PYTHON_BIN="${PYTHON:-}"
+
+if [[ -z "$PYTHON_BIN" ]]; then
+  if command -v python3 >/dev/null 2>&1; then
+    PYTHON_BIN="$(command -v python3)"
+  elif command -v python >/dev/null 2>&1; then
+    PYTHON_BIN="$(command -v python)"
+  else
+    echo "error: python3/python not found in PATH" >&2
+    exit 1
+  fi
+fi
+
+mkdir -p "$APP_HOME" "$BIN_DIR"
+
+"$PYTHON_BIN" -m venv "$VENV_DIR"
+"$VENV_DIR/bin/python" -m pip install --upgrade pip setuptools wheel
+"$VENV_DIR/bin/python" -m pip install --upgrade "$(pwd)"
+
+cat >"$LAUNCHER" <<EOF
+#!/usr/bin/env bash
+exec "$VENV_DIR/bin/coinhunter" "\$@"
+EOF
+chmod +x "$LAUNCHER"
+
+echo "Installed coinhunter into:"
+echo "  venv: $VENV_DIR"
+echo "  launcher: $LAUNCHER"