refactor!: rename the project from Monitor to MoShiro [CI]

Namespaces, assemblies, solution, binaries, images, systemd units, config paths, environment variables, protocol methods and the Linux user are all renamed. Breaking: existing databases, node identities and installed units must be recreated.

backend/fleet/src/Fleet.Server.Abstractions/IFleetStore.cs

@@ -2,7 +2,7 @@ using Fleet.Core;
 
 namespace Fleet.Server;
 
-/// <summary>Fleet 服务端需要的存储。产品可以自己实现（Monitor 把它放进 monitor.db）。</summary>
+/// <summary>Fleet 服务端需要的存储。产品可以自己实现（MoShiro 把它放进 moshiro.db）。</summary>
 public interface IFleetStore
 {
     ValueTask<JoinTokenRecord?> FindJoinTokenAsync(ReadOnlyMemory<byte> tokenSha256, CancellationToken ct);