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/import_params.rs

@@ -48,6 +48,7 @@ pub struct ImportParams {
 	pub wasm_method: WasmExecutionMethod,
 
 	/// The WASM instantiation method to use.
+	///
 	/// Only has an effect when `wasm-execution` is set to `compiled`.
 	/// The copy-on-write strategies are only supported on Linux.
 	/// If the copy-on-write variant of a strategy is unsupported
@@ -65,6 +66,7 @@ pub struct ImportParams {
 	pub wasmtime_instantiation_strategy: WasmtimeInstantiationStrategy,
 
 	/// Specify the path where local WASM runtimes are stored.
+	///
 	/// These runtimes will override on-chain runtimes when the version matches.
 	#[arg(long, value_name = "PATH")]
 	pub wasm_runtime_overrides: Option<PathBuf>,
@@ -74,12 +76,12 @@ pub struct ImportParams {
 	pub execution_strategies: ExecutionStrategiesParams,
 
 	/// Specify the state cache size.
+	///
 	/// Providing `0` will disable the cache.
 	#[arg(long, value_name = "Bytes", default_value_t = 67108864)]
 	pub trie_cache_size: usize,
 
-	/// DEPRECATED
-	/// Switch to `--trie-cache-size`.
+	/// DEPRECATED: switch to `--trie-cache-size`.
 	#[arg(long)]
 	state_cache_size: Option<usize>,
 }
@@ -115,26 +117,23 @@ impl ImportParams {
 /// Execution strategies parameters.
 #[derive(Debug, Clone, Args)]
 pub struct ExecutionStrategiesParams {
-	/// The means of execution used when calling into the runtime for importing blocks as
-	/// part of an initial sync.
+	/// Runtime execution strategy for importing blocks during initial sync.
 	#[arg(long, value_name = "STRATEGY", value_enum, ignore_case = true)]
 	pub execution_syncing: Option<ExecutionStrategy>,
 
-	/// The means of execution used when calling into the runtime for general block import
-	/// (including locally authored blocks).
+	/// Runtime execution strategy for general block import (including locally authored blocks).
 	#[arg(long, value_name = "STRATEGY", value_enum, ignore_case = true)]
 	pub execution_import_block: Option<ExecutionStrategy>,
 
-	/// The means of execution used when calling into the runtime while constructing blocks.
+	/// Runtime execution strategy for constructing blocks.
 	#[arg(long, value_name = "STRATEGY", value_enum, ignore_case = true)]
 	pub execution_block_construction: Option<ExecutionStrategy>,
 
-	/// The means of execution used when calling into the runtime while using an off-chain worker.
+	/// Runtime execution strategy for offchain workers.
 	#[arg(long, value_name = "STRATEGY", value_enum, ignore_case = true)]
 	pub execution_offchain_worker: Option<ExecutionStrategy>,
 
-	/// The means of execution used when calling into the runtime while not syncing, importing or
-	/// constructing blocks.
+	/// Runtime execution strategy when not syncing, importing or constructing blocks.
 	#[arg(long, value_name = "STRATEGY", value_enum, ignore_case = true)]
 	pub execution_other: Option<ExecutionStrategy>,