common/prque: generic priority queue (#26290)

* common, core, eth, les, trie: make prque generic

* les/vflux/server: fixed issues in priorityPool

* common, core, eth, les, trie: make priority also generic in prque

* les/flowcontrol: add test case for priority accumulator overflow

* les/flowcontrol: avoid priority value overflow

* common/prque: use int priority in some tests

No need to convert to int64 when we can just change the type used by the
queue.

* common/prque: remove comment about int64 range

---------

Co-authored-by: Zsolt Felfoldi <zsfelfoldi@gmail.com>
Co-authored-by: Felix Lange <fjl@twurst.com>

trie/sync.go

@@ -160,7 +160,7 @@ type Sync struct {
 	membatch *syncMemBatch                // Memory buffer to avoid frequent database writes
 	nodeReqs map[string]*nodeRequest      // Pending requests pertaining to a trie node path
 	codeReqs map[common.Hash]*codeRequest // Pending requests pertaining to a code hash
-	queue    *prque.Prque                 // Priority queue with the pending requests
+	queue    *prque.Prque[int64, any]     // Priority queue with the pending requests
 	fetches  map[int]int                  // Number of active fetches per trie node depth
 }
 
@@ -172,7 +172,7 @@ func NewSync(root common.Hash, database ethdb.KeyValueReader, callback LeafCallb
 		membatch: newSyncMemBatch(),
 		nodeReqs: make(map[string]*nodeRequest),
 		codeReqs: make(map[common.Hash]*codeRequest),
-		queue:    prque.New(nil),
+		queue:    prque.New[int64, any](nil), // Ugh, can contain both string and hash, whyyy
 		fetches:  make(map[int]int),
 	}
 	ts.AddSubTrie(root, nil, common.Hash{}, nil, callback)