fix(cli/cmd): update operator init-nodes cmd

[kc1116]

This PR updates the flags for the operator init-nodes cmd so that the cmd can be run directly from source without having to install the omni CLI. This PR adds a new flag --halo-tag, which is the halo tag to use for the new node. This is required because the current buildinfo.GitCommit() func will return an err if the cmd is not run from an binary. This PR also binds the current --feature-flags to the init-nodes command. Now we can run the command in CI and locally as follows

cd cli/cmd/omni
go run main.go operator init-nodes --network=staging \
--moniker=foo \
--home=/tmp \
--halo-tag=main \
--feature-flags=evmstaking

issue: none