[swarm] Register templates on startup if not already registered

[sdbondi]

Nice to have.
Suggest a cli arg that points to a wasm file or directory containing .wasm files.

When registering VNs initially, before mining the VNs into the epoch, register the provided wasm file(s) and mine everything in.

This avoids having to manually upload templates each time we start from fresh during development. This helps with tari swap bench which requires some templates to exist.