fix: lifecycle-safe logger teardown without global state

Store file handle per module, swap lifecycle logger before closing file,
return teardown errors, remove duplicate Module() func.

Co-authored-by: Cursor <cursoragent@cursor.com>

doc.go

@@ -0,0 +1,6 @@
+// Package applog configures slog for [gitea.auvem.com/go-toolkit/app.Lifecycle]
+// with optional JSON file output and tint console formatting.
+//
+// Teardown closes the log file and re-points the lifecycle logger to console-only
+// (or discard if console is disabled) so post-teardown lifecycle logs remain safe.
+package applog