chore: use range-over-integer (Go 1.22+)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

chain/difficulty.go

@@ -48,7 +48,7 @@ func (c *Chain) NextDifficulty(height uint64, forks []config.HardFork) (uint64,
 	timestamps := make([]uint64, count)
 	cumulDiffs := make([]*big.Int, count)
 
-	for i := 0; i < count; i++ {
+	for i := range count {
 		meta, err := c.getBlockMeta(startHeight + uint64(i))
 		if err != nil {
 			// Fewer blocks than expected — use what we have.

consensus/pow.go

@@ -27,7 +27,7 @@ func CheckDifficulty(hash types.Hash, difficulty uint64) bool {
 	// Convert hash to big.Int (little-endian as per CryptoNote convention).
 	// Reverse to big-endian for big.Int.
 	var be [32]byte
-	for i := 0; i < 32; i++ {
+	for i := range 32 {
 		be[i] = hash[31-i]
 	}
 	hashInt := new(big.Int).SetBytes(be[:])

p2p/handshake.go

@@ -79,7 +79,7 @@ type PeerlistEntry struct {
 func DecodePeerlist(blob []byte) []PeerlistEntry {
 	n := len(blob) / PeerlistEntrySize
 	entries := make([]PeerlistEntry, n)
-	for i := 0; i < n; i++ {
+	for i := range n {
 		off := i * PeerlistEntrySize
 		entries[i] = PeerlistEntry{
 			IP:       binary.LittleEndian.Uint32(blob[off : off+4]),

p2p/relay.go

@@ -252,7 +252,7 @@ func (r *ResponseChainEntry) Decode(data []byte) error {
 func splitHashes(blob []byte, size int) [][]byte {
 	n := len(blob) / size
 	out := make([][]byte, n)
-	for i := 0; i < n; i++ {
+	for i := range n {
 		out[i] = blob[i*size : (i+1)*size]
 	}
 	return out

tui/explorer_model.go

@@ -362,7 +362,7 @@ func (m *ExplorerModel) loadBlocks() {
 	}
 
 	rows := make([]blockRow, count)
-	for i := 0; i < count; i++ {
+	for i := range count {
 		h := height - 1 - uint64(i)
 		blk, meta, err := m.chain.GetBlockByHeight(h)
 		if err != nil {

types/address.go

@@ -170,7 +170,7 @@ func base58Encode(data []byte) string {
 	fullBlocks := len(data) / 8
 	lastBlockSize := len(data) % 8
 
-	for i := 0; i < fullBlocks; i++ {
+	for i := range fullBlocks {
 		block := data[i*8 : (i+1)*8]
 		encoded := encodeBlock(block, 11)
 		result = append(result, encoded...)
@@ -227,7 +227,7 @@ func base58Decode(s string) ([]byte, error) {
 
 	var result []byte
 
-	for i := 0; i < fullBlocks; i++ {
+	for i := range fullBlocks {
 		blockStr := s[i*11 : (i+1)*11]
 		decoded, err := decodeBlock(blockStr, 8)
 		if err != nil {

wallet/mnemonic.go

@@ -49,7 +49,7 @@ func MnemonicDecode(phrase string) ([32]byte, error) {
 
 	n := uint32(numWords)
 
-	for i := 0; i < 8; i++ {
+	for i := range 8 {
 		w1, ok1 := wordIndex[words[i*3]]
 		w2, ok2 := wordIndex[words[i*3+1]]
 		w3, ok3 := wordIndex[words[i*3+2]]

wire/decoder.go

@@ -55,7 +55,7 @@ func (d *Decoder) ReadVarint() uint64 {
 	}
 	var val uint64
 	var shift uint
-	for i := 0; i < MaxVarintLen; i++ {
+	for range MaxVarintLen {
 		_, d.err = io.ReadFull(d.r, d.buf[:1])
 		if d.err != nil {
 			return 0