fix(logging): don't duplicate manager group key

I'd never realized this before, but `.With()` is append only, and so
re-adding a set of kvs under an existing group adds a second group with
the new entries -- it does not combine them in the json object or add
the keys to the existing group like I had for some reason thought.

This fixes that by only setting the kvs for that group once.

cmd/mango/mango.go

@@ -146,14 +146,7 @@ func mango(ctx context.Context, logger *slog.Logger, inventoryPath, hostname str
 	inv.Reload(ctx, inventoryLogger)
 
 	// start manager, reload it with data from inventory, and then start a run of everything for the system
-	managerLogger := logger.With(
-		slog.String("worker", "manager"),
-		slog.Group(
-			"manager",
-			slog.String("inventory", inventoryPath),
-			slog.String("hostname", hostname),
-		),
-	)
+	managerLogger := logger.With(slog.String("worker", "manager"))
 	managerLogger.LogAttrs(
 		ctx,
 		slog.LevelInfo,

internal/manager/manager.go

@@ -89,6 +89,8 @@ func (mgr *Manager) ReloadAndRunAll(ctx context.Context, logger *slog.Logger, in
 	mLogger := logger.With(
 		slog.Group(
 			"manager",
+			slog.String("inventory", inv.GetInventoryPath()),
+			slog.String("hostname", inv.GetHostname()),
 			slog.Bool(string(contextKeyEnrolled), enrolled),
 			slog.String(string(contextKeyRunID), runID.String()),
 		),