Ensure min and max block number is for consensus blocks

Adding `WHERE consensus = true` both fixes the bug that
`min_block_number` and `max_block_number` were including non-consensus
blocks, but it also makes the query faster because there is an index
for consensus blocks.

Times from Eth Mainnet production:

```
ether=> SELECT min(b0."number") FROM "blocks" AS b0;
 min
-----
   0
(1 row)

Time: 414.218 ms
ether=> EXPLAIN SELECT min(b0."number") FROM "blocks" AS b0;
                                          QUERY PLAN
-----------------------------------------------------------------------------------------------
 Finalize Aggregate  (cost=223454.95..223454.96 rows=1 width=8)
   ->  Gather  (cost=223454.73..223454.95 rows=2 width=8)
         Workers Planned: 2
         ->  Partial Aggregate  (cost=222454.73..222454.74 rows=1 width=8)
               ->  Parallel Seq Scan on blocks b0  (cost=0.00..215051.99 rows=2961099 width=8)
(5 rows)

Time: 1.040 ms
ether=> EXPLAIN SELECT min(b0."number") FROM "blocks" AS b0 WHERE b0.consensus = true;
                                                         QUERY PLAN
-----------------------------------------------------------------------------------------------------------------------------
 Result  (cost=0.45..0.46 rows=1 width=8)
   InitPlan 1 (returns $0)
     ->  Limit  (cost=0.43..0.45 rows=1 width=8)
           ->  Index Only Scan using one_consensus_block_at_height on blocks b0  (cost=0.43..158050.90 rows=7045520 width=8)
                 Index Cond: (number IS NOT NULL)
(5 rows)

Time: 3.350 ms
ether=> SELECT min(b0."number") FROM "blocks" AS b0 WHERE b0.consensus = true;
 min
-----
   0
(1 row)

Time: 1.059 ms
```

apps/block_scout_web/lib/block_scout_web/controllers/api/rpc/logs_controller.ex

@@ -183,7 +183,7 @@ defmodule BlockScoutWeb.API.RPC.LogsController do
   defp to_block_number(params, param_key) do
     case params[param_key] do
       "latest" ->
-        Chain.max_block_number()
+        Chain.consensus_block_number(:max)
 
       _ ->
         to_integer(params, param_key)

apps/block_scout_web/lib/block_scout_web/controllers/api/rpc/transaction_controller.ex

@@ -83,7 +83,7 @@ defmodule BlockScoutWeb.API.RPC.TransactionController do
   end
 
   defp max_block_number do
-    case Chain.max_block_number() do
+    case Chain.consensus_block_number(:max) do
       {:ok, number} -> number
       {:error, :not_found} -> 0
     end

apps/block_scout_web/lib/block_scout_web/controllers/block_transaction_controller.ex

@@ -82,7 +82,7 @@ defmodule BlockScoutWeb.BlockTransactionController do
   defp block_above_tip?("0x" <> _), do: nil
 
   defp block_above_tip?(block_hash_or_number) when is_binary(block_hash_or_number) do
-    with {:ok, max_block_number} <- Chain.max_block_number() do
+    with {:ok, max_block_number} <- Chain.consensus_block_number(:max) do
       {block_number, _} = Integer.parse(block_hash_or_number)
       block_number > max_block_number
     else

apps/block_scout_web/lib/block_scout_web/controllers/transaction_internal_transaction_controller.ex

@@ -65,7 +65,7 @@ defmodule BlockScoutWeb.TransactionInternalTransactionController do
   end
 
   defp max_block_number do
-    case Chain.max_block_number() do
+    case Chain.consensus_block_number(:max) do
       {:ok, number} -> number
       {:error, :not_found} -> 0
     end

apps/block_scout_web/lib/block_scout_web/controllers/transaction_log_controller.ex

@@ -61,7 +61,7 @@ defmodule BlockScoutWeb.TransactionLogController do
   end
 
   defp max_block_number do
-    case Chain.max_block_number() do
+    case Chain.consensus_block_number(:max) do
       {:ok, number} -> number
       {:error, :not_found} -> 0
     end

apps/block_scout_web/lib/block_scout_web/controllers/transaction_token_transfer_controller.ex

@@ -65,7 +65,7 @@ defmodule BlockScoutWeb.TransactionTokenTransferController do
   end
 
   defp max_block_number do
-    case Chain.max_block_number() do
+    case Chain.consensus_block_number(:max) do
       {:ok, number} -> number
       {:error, :not_found} -> 0
     end

apps/explorer/lib/explorer/chain.ex

@@ -845,8 +845,8 @@ defmodule Explorer.Chain do
   """
   @spec indexed_ratio() :: float()
   def indexed_ratio do
-    with {:ok, min_block_number} <- min_block_number(),
-         {:ok, max_block_number} <- max_block_number() do
+    with {:ok, min_block_number} <- consensus_block_number(:min),
+         {:ok, max_block_number} <- consensus_block_number(:max) do
       indexed_blocks = max_block_number - min_block_number + 1
       indexed_blocks / (max_block_number + 1)
     else
@@ -1156,48 +1156,40 @@ defmodule Explorer.Chain do
   end
 
   @doc """
-  The maximum `t:Explorer.Chain.Block.t/0` `number`
+  Aggregate of consensus block numbers.
 
-  If blocks are skipped and inserted out of number order, the max number is still returned
+  If blocks are skipped and inserted out of number order, the `:max` and `:min` numbers are still returned
 
       iex> insert(:block, number: 2)
       iex> insert(:block, number: 1)
-      iex> Explorer.Chain.max_block_number()
+      iex> Explorer.Chain.consensus_block_number(:min)
+      {:ok, 1}
+      iex> Explorer.Chain.consensus_block_number(:max)
       {:ok, 2}
 
-  If there are no blocks, `{:error, :not_found}` is returned
-
-      iex> Explorer.Chain.max_block_number()
-      {:error, :not_found}
-
-  """
-  @spec max_block_number() :: {:ok, Block.block_number()} | {:error, :not_found}
-  def max_block_number do
-    case Repo.aggregate(Block, :max, :number) do
-      nil -> {:error, :not_found}
-      number -> {:ok, number}
-    end
-  end
-
-  @doc """
-  The minimum `t:Explorer.Chain.Block.t/0` `number` (used to show loading status while indexing)
-
-  If blocks are skipped and inserted out of number order, the min number is still returned
+  Non-consensus blocks are ignored
 
-      iex> insert(:block, number: 2)
-      iex> insert(:block, number: 1)
-      iex> Explorer.Chain.min_block_number()
-      {:ok, 1}
+      iex> insert(:block, number: 3, consensus: false)
+      iex> insert(:block, number: 2, consensus: true)
+      iex> insert(:block, number: 1, consensus: false)
+      iex> Explorer.Chain.consensus_block_number(:min)
+      {:ok, 2}
+      iex> Explorer.Chain.consensus_block_number(:max)
+      {:ok, 2}
 
   If there are no blocks, `{:error, :not_found}` is returned
 
-      iex> Explorer.Chain.min_block_number()
+      iex> Explorer.Chain.consensus_block_number(:min)
+      {:error, :not_found}
+      iex> Explorer.Chain.consensus_block_number(:max)
       {:error, :not_found}
 
   """
-  @spec min_block_number() :: {:ok, Block.block_number()} | {:error, :not_found}
-  def min_block_number do
-    case Repo.aggregate(Block, :min, :number) do
+  def consensus_block_number(aggregate) do
+    Block
+    |> where(consensus: true)
+    |> Repo.aggregate(aggregate, :number)
+    |> case do
       nil -> {:error, :not_found}
       number -> {:ok, number}
     end

apps/explorer/lib/explorer/chain/supply/proof_of_authority.ex

@@ -41,7 +41,7 @@ defmodule Explorer.Chain.Supply.ProofOfAuthority do
   end
 
   defp block_height do
-    case Chain.max_block_number() do
+    case Chain.consensus_block_number(:max) do
       {:ok, height} -> height
       _ -> 0
     end

apps/explorer/lib/explorer/etherscan.ex

@@ -43,7 +43,7 @@ defmodule Explorer.Etherscan do
         %Hash{byte_count: unquote(Hash.Address.byte_count())} = address_hash,
         options \\ @default_options
       ) do
-    case Chain.max_block_number() do
+    case Chain.consensus_block_number(:max) do
       {:ok, max_block_number} ->
         merged_options = Map.merge(@default_options, options)
         list_transactions(address_hash, max_block_number, merged_options)
@@ -152,7 +152,7 @@ defmodule Explorer.Etherscan do
         contract_address_hash,
         options \\ @default_options
       ) do
-    case Chain.max_block_number() do
+    case Chain.consensus_block_number(:max) do
       {:ok, max_block_number} ->
         merged_options = Map.merge(@default_options, options)
         list_token_transfers(address_hash, contract_address_hash, max_block_number, merged_options)

apps/explorer/test/explorer/chain_test.exs

@@ -594,7 +594,7 @@ defmodule Explorer.ChainTest do
   describe "confirmations/1" do
     test "with block.number == max_block_number " do
       block = insert(:block)
-      {:ok, max_block_number} = Chain.max_block_number()
+      {:ok, max_block_number} = Chain.consensus_block_number(:max)
 
       assert block.number == max_block_number
       assert Chain.confirmations(block, max_block_number: max_block_number) == 0

apps/explorer/test/explorer/etherscan_test.exs

@@ -122,7 +122,7 @@ defmodule Explorer.EtherscanTest do
 
       [found_transaction] = Etherscan.list_transactions(address.hash)
 
-      {:ok, max_block_number} = Chain.max_block_number()
+      {:ok, max_block_number} = Chain.consensus_block_number(:max)
       expected_confirmations = max_block_number - transaction.block_number
 
       assert found_transaction.confirmations == expected_confirmations
@@ -888,7 +888,7 @@ defmodule Explorer.EtherscanTest do
 
       [found_token_transfer] = Etherscan.list_token_transfers(token_transfer.from_address_hash, nil)
 
-      {:ok, max_block_number} = Chain.max_block_number()
+      {:ok, max_block_number} = Chain.consensus_block_number(:max)
       expected_confirmations = max_block_number - transaction.block_number
 
       assert found_token_transfer.confirmations == expected_confirmations

apps/indexer/lib/indexer.ex

@@ -22,7 +22,7 @@ defmodule Indexer do
 
   """
   def max_block_number do
-    case Chain.max_block_number() do
+    case Chain.consensus_block_number(:max) do
       {:ok, number} -> number
       {:error, :not_found} -> 0
     end