feat(blocksync): sort peers by download rate & multiple requests for …

…closer blocks (backport #2475) (#2575)

This is an automatic backport of pull request #2475 done by
[Mergify](https://mergify.com).


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Co-authored-by: Anton Kaliaev <anton.kalyaev@gmail.com>

.changelog/unreleased/improvements/2475-blocksync-2nd-request.md

@@ -0,0 +1,3 @@
+- `[blocksync]` Request a block from peer B if we are approaching pool's height
+  (less than 50 blocks) and the current peer A is slow in sending us the
+  block [\#2475](https://github.com/cometbft/cometbft/pull/2475)

.changelog/unreleased/improvements/2475-blocksync-no-block-response.md

@@ -0,0 +1,3 @@
+- `[blocksync]` Request the block N from peer B immediately after getting
+  `NoBlockResponse` from peer A
+  [\#2475](https://github.com/cometbft/cometbft/pull/2475)

.changelog/unreleased/improvements/2475-blocksync-sort-peers.md

@@ -0,0 +1,2 @@
+- `[blocksync]` Sort peers by download rate (the fastest peer is picked first)
+  [\#2475](https://github.com/cometbft/cometbft/pull/2475)