feat(`config`): add `[labels]` section to `foundry.toml`

### Component

Other (please describe)

### Describe the feature you would like

By giving alias to frequently interacted contracts in `foundry.toml`, say [labels], could facilitate development even more. Imagine this feature as a combination of two existing feature. The first is giving alias to rpc_endpoints by `[rpc_endpoint]` field in `foundry.toml`; the second is giving alias to addresses by `vm.label` in scripts and tests.

Being able to use the label in cast commands, say `cast send -r eth MAINNET_CONTRACT_I_CARE ...`, could already save some time copy and pasting. It also helps the readability.

A further step could be extending the configured labels to all the tests and scripts as if it's in `function setup()`, saving the time of repeatedly using of `vm.label`

### Additional context

_No response_