Improve Client CLI help readability (#2073)

Currently the CLI `-h/--help` commad output is almost unreadable as (for
some commands) it:
- doesn't provide a short brief of what the command does.
- doesn't separate the options description in smaller paragraphs.
- doesn't use a smart wrap strategy for lines longer than the number of
columns in the terminal.

Follow some pics taken with a 100 cols wide term

## Short help (./node -h)

### Before


![20231028-174531-grim](https://github.com/paritytech/polkadot-sdk/assets/8143589/11b62c3c-dcd5-43f4-ac58-f1b299e3f4b9)

### After


![20231028-175041-grim](https://github.com/paritytech/polkadot-sdk/assets/8143589/dc08f6fd-b287-40fb-8b33-71a185922104)


## Long help (./node --help)

### Before


![20231028-175257-grim](https://github.com/paritytech/polkadot-sdk/assets/8143589/9ebdc0ae-54ee-4760-b873-a7e813523cb6)

### After


![20231028-175155-grim](https://github.com/paritytech/polkadot-sdk/assets/8143589/69cbe5cb-eb2f-46a5-8ebf-76c0cf8c4bad)

---------

Co-authored-by: command-bot <>

substrate/client/cli/src/params/runtime_params.rs

@@ -22,7 +22,9 @@ use std::str::FromStr;
 /// Parameters used to config runtime.
 #[derive(Debug, Clone, Args)]
 pub struct RuntimeParams {
-	/// The size of the instances cache for each runtime. The values higher than 32 are illegal.
+	/// The size of the instances cache for each runtime [max: 32].
+	///
+	/// Values higher than 32 are illegal.
 	#[arg(long, default_value_t = 8, value_parser = parse_max_runtime_instances)]
 	pub max_runtime_instances: usize,