Switch cmd/ to use constructor functions. (#36962)

This is a step towards potentially splitting command groups into their
own folders to clean up `cmd/` as one folder for all cli commands.
Returning fresh command instances will also aid in adding tests as you
don't need to concern yourself with the whole command tree being one
mutable variable.

---------

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

cmd/manager.go

@@ -13,22 +13,24 @@ import (
 	"github.com/urfave/cli/v3"
 )
 
-var (
-	// CmdManager represents the manager command
-	CmdManager = &cli.Command{
+func newManagerCommand() *cli.Command {
+	return &cli.Command{
 		Name:        "manager",
 		Usage:       "Manage the running gitea process",
 		Description: "This is a command for managing the running gitea process",
 		Commands: []*cli.Command{
-			subcmdShutdown,
-			subcmdRestart,
-			subcmdReloadTemplates,
-			subcmdFlushQueues,
-			subcmdLogging,
-			subCmdProcesses,
+			newShutdownCommand(),
+			newRestartCommand(),
+			newReloadTemplatesCommand(),
+			newFlushQueuesCommand(),
+			newLoggingCommand(),
+			newProcessesCommand(),
 		},
 	}
-	subcmdShutdown = &cli.Command{
+}
+
+func newShutdownCommand() *cli.Command {
+	return &cli.Command{
 		Name:  "shutdown",
 		Usage: "Gracefully shutdown the running process",
 		Flags: []cli.Flag{
@@ -38,7 +40,10 @@ var (
 		},
 		Action: runShutdown,
 	}
-	subcmdRestart = &cli.Command{
+}
+
+func newRestartCommand() *cli.Command {
+	return &cli.Command{
 		Name:  "restart",
 		Usage: "Gracefully restart the running process - (not implemented for windows servers)",
 		Flags: []cli.Flag{
@@ -48,7 +53,10 @@ var (
 		},
 		Action: runRestart,
 	}
-	subcmdReloadTemplates = &cli.Command{
+}
+
+func newReloadTemplatesCommand() *cli.Command {
+	return &cli.Command{
 		Name:  "reload-templates",
 		Usage: "Reload template files in the running process",
 		Flags: []cli.Flag{
@@ -58,7 +66,10 @@ var (
 		},
 		Action: runReloadTemplates,
 	}
-	subcmdFlushQueues = &cli.Command{
+}
+
+func newFlushQueuesCommand() *cli.Command {
+	return &cli.Command{
 		Name:   "flush-queues",
 		Usage:  "Flush queues in the running process",
 		Action: runFlushQueues,
@@ -77,7 +88,10 @@ var (
 			},
 		},
 	}
-	subCmdProcesses = &cli.Command{
+}
+
+func newProcessesCommand() *cli.Command {
+	return &cli.Command{
 		Name:   "processes",
 		Usage:  "Display running processes within the current process",
 		Action: runProcesses,
@@ -107,7 +121,7 @@ var (
 			},
 		},
 	}
-)
+}
 
 func runShutdown(ctx context.Context, c *cli.Command) error {
 	setup(ctx, c.Bool("debug"))