feat: add list_plugins admin RPC and remove rpc_addr admin RPC method from trait

[0xsouravm]

Changes:

• Added list_plugins(meta) RPC method definition
• Extended PluginManagerCommand enum with ListPlugins variant
• Updated plugin_uuid_map: HashMap<Uuid, usize> into `plugin_map: HashMap<Uuid, (usize, String)>to store plugin names along with UUID for efficient listing
• Removed rpc_addr method from the trait

Reference: #330

[MicaiahReid]

As I was reviewing this PR, I realized the rpc_addr method is quite a silly one 😂

You need to know the network's rpc address in order to fetch it's rpc address via rpc... so why do we need the method? hahaha

Would you be able to remove the changes from that method, and that method from the AdminRpc trait completely?

[0xsouravm]

As I was reviewing this PR, I realized the rpc_addr method is quite a silly one 😂

You need to know the network's rpc address in order to fetch it's rpc address via rpc... so why do we need the method? hahaha

Would you be able to remove the changes from that method, and that method from the AdminRpc trait completely?

When put that way, it does sound funny. 😹 . Sure I will remove all instances of the method and the structure field I added to tests and elsewhere!

[0xsouravm]

@MicaiahReid I have added the changes you requested. Please take a look!

[MicaiahReid]

LGTM, thanks @0xsouravm!!