feat: base layer scanner fetches templates from the base layer

[mrnaveira]

Description

• base_layer_client.rs: added a method to get template registrations since a specific height.
• base_layer_scanner.rs: fetch the template registrations since the last scan.
• template_manager.rs: refactor to use base layer types for template registrations.
• main.rs: reordered the json-rpc up so it's not blocked by the dan node services.

Motivation and Context

Until now, the base layer scanner in the VN did not fetch real templates from the base layer as the base layer did not store or allow retrieval of templates.

With #4726 in the base layer, we have now a gRPC method to query data of newly published templates since a specific block height.

So this PR updates the base layer scanner and template manager to fetch real templates from the base layer.

How Has This Been Tested?

Manually:

1. Published a sample template through the wallet gRPC.
2. The base layer (with the changes from #4726) does detect, store in lmdb and allow fetching the sample template.
3. The base layer scanner in the VN does retrieve the template metadata and attempt fetching the binary from the url.