feat: port engine lib modules (log, sys, tpl, host)

engine/lib/log.py

@@ -0,0 +1,19 @@
+# engine/lib/log.py
+"""ctx.log — [node] [action] [level] message (port of root_log_*)."""
+from __future__ import annotations
+import sys
+
+
+class Log:
+    def __init__(self, node: str = "global", action: str = "core"):
+        self.node = node
+        self.action = action
+
+    def _emit(self, level: str, msg: str, stream=None) -> None:
+        print(f"[{self.node}] [{self.action}] [{level}] {msg}",
+              file=stream or sys.stdout, flush=True)
+
+    def info(self, msg): self._emit("INFO", msg)
+    def warn(self, msg): self._emit("WARN", msg)
+    def error(self, msg): self._emit("ERROR", msg, sys.stderr)
+    def success(self, msg): self._emit("SUCCESS", msg)