Docs only changes (#9258)

* Docs changes to improve clarity

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

Co-authored-by: Guillaume Thiolliere <gui.thiolliere@gmail.com>

substrate/client/transaction-pool/graph/src/ready.rs

@@ -108,11 +108,13 @@ Hence every hash retrieved from `provided_tags` is always present in `ready`;
 qed
 "#;
 
+/// Validated transactions that are block ready with all their dependencies met.
 #[derive(Debug, parity_util_mem::MallocSizeOf)]
 pub struct ReadyTransactions<Hash: hash::Hash + Eq, Ex> {
-	/// Insertion id
+	/// Next free insertion id (used to indicate when a transaction was inserted into the pool).
 	insertion_id: u64,
 	/// tags that are provided by Ready transactions
+	/// (only a single transaction can provide a specific tag)
 	provided_tags: HashMap<Tag, Hash>,
 	/// Transactions that are ready (i.e. don't have any requirements external to the pool)
 	ready: TrackedMap<Hash, ReadyTx<Hash, Ex>>,
@@ -235,7 +237,7 @@ impl<Hash: hash::Hash + Member + Serialize, Ex> ReadyTransactions<Hash, Ex> {
 			.fold(None, f)
 	}
 
-	/// Returns true if given hash is part of the queue.
+	/// Returns true if given transaction is part of the queue.
 	pub fn contains(&self, hash: &Hash) -> bool {
 		self.ready.read().contains_key(hash)
 	}

substrate/client/transaction-pool/graph/src/watcher.rs

@@ -24,10 +24,11 @@ use sp_utils::mpsc::{tracing_unbounded, TracingUnboundedSender, TracingUnbounded
 
 /// Extrinsic watcher.
 ///
-/// Represents a stream of status updates for particular extrinsic.
+/// Represents a stream of status updates for a particular extrinsic.
 #[derive(Debug)]
 pub struct Watcher<H, BH> {
 	receiver: TracingUnboundedReceiver<TransactionStatus<H, BH>>,
+	/// transaction hash of watched extrinsic
 	hash: H,
 }