Fix incorrect CLI examples in README

[ABresting]

Problem

The README documents CLI commands that don't match actual usage:

1. Transfer command missing submit subcommand

README says:

./target/release/setu transfer --from <FROM> --to <TO> --amount 100

Actual usage:

./target/release/setu transfer submit --from <FROM> --to <TO> --amount 100

2. setu balance command doesn't exist

README says:

./target/release/setu balance --address <ADDRESS>

Actual: There is no balance CLI command. Balance is only available via HTTP API:

curl http://localhost:8080/api/v1/state/balance/<ADDRESS>

Fix

• Update the "Submit Transactions (CLI)" section in README.md
• Replace setu transfer --from with setu transfer submit --from
• Replace setu balance --address with the curl equivalent