[test] fork_profile_parses_and_targets_localhost missing chain_id, metrics bind, profit gate asserts

[obchain]

Refs #52

File: crates/charon-core/tests/config_profiles.rs

Problem

Test verifies fork.toml parses + rpc targets localhost. Does NOT assert:

• chain_id = 56
• metrics.bind = 127.0.0.1:9091
• bot.min_profit_usd < default (the intentional lowering)
• presence of required Venus addresses

Silent drift in any of these fields passes the test.

Fix

Add assertions:

assert_eq!(cfg.chain.bnb.chain_id, 56);
assert_eq!(cfg.metrics.bind, "127.0.0.1:9091");
assert!(cfg.bot.min_profit_usd < 5.0);
assert_eq!(cfg.protocol.venus.comptroller, address!("fd36e2c2a6789db23113685031d7f16329158384"));

[obchain]

Fixed on feat/24-anvil-fork (fe60699): crates/charon-core/tests/config_profiles.rs::fork_profile_parses_and_targets_localhost now asserts: chain_id == 56, ws_url and http_url both loopback-prefixed, metrics.bind IP is loopback (not 0.0.0.0), profile_tag == Some("fork"), Config::validate accepts the profile, liquidator map is empty (locks in the dropped address(0) placeholder), and min_profit_usd is strictly lower than default.toml's — parsed in the same test so an accidental bump fails loud.