fix: address review comments

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: ovitrif

app/src/main/java/to/bitkit/ext/Lnurl.kt

@@ -28,7 +28,7 @@ fun LnurlPayData.isFixedAmount(): Boolean =
  * For variable-amount requests the user-selected sat amount is converted to msats.
  */
 fun LnurlPayData.callbackAmountMsats(userSats: ULong? = null): ULong =
-    if (isFixedAmount()) minSendable else (userSats ?: minSendableSat()) * 1000u
+    if (isFixedAmount()) minSendable else (userSats ?: minSendableSat()) * MSat.PER_SAT
 
 fun LnurlWithdrawData.minWithdrawableSat(): ULong = MSat(minWithdrawable ?: 0u).ceil()
 fun LnurlWithdrawData.maxWithdrawableSat(): ULong = MSat(maxWithdrawable).floor()

app/src/main/java/to/bitkit/models/MSat.kt

@@ -1,19 +1,20 @@
 package to.bitkit.models
 
 /**
- * A wrapper for millisatoshi [ULong] values that provides explicit sat conversions.
+ * A non-boxing wrapper for millisatoshi [ULong] values that provides explicit sat conversions.
  *
- * Eliminates scattered `/ 1000u` and `(x + 999u) / 1000u` patterns by encoding
- * the rounding intent directly in the API: [ceil] rounds up, [floor] truncates.
- *
- * Zero runtime overhead — this is an [inline value class][JvmInline].
+ * Encapsulates the rounding intent directly in the API: [ceil] rounds up, [floor] truncates.
  */
 @JvmInline
 value class MSat(val value: ULong) {
 
+    companion object {
+        const val PER_SAT: ULong = 1000u
+    }
+
     /** Round up to the nearest whole sat. Use for payment/display amounts. */
-    fun ceil(): ULong = (value + 999u) / 1000u
+    fun ceil(): ULong = (value + PER_SAT - 1u) / PER_SAT
 
     /** Truncate sub-sat remainder. Use for fees and upper bounds. */
-    fun floor(): ULong = value / 1000u
+    fun floor(): ULong = value / PER_SAT
 }

app/src/main/java/to/bitkit/ui/NodeInfoScreen.kt

@@ -361,7 +361,9 @@ private fun ChannelsSection(
                 )
                 ChannelDetailRow(
                     title = stringResource(R.string.lightning__inbound_htlc_max),
-                    value = "₿ ${(channel.inboundHtlcMaximumMsat?.let { MSat(it).floor() } ?: 0u).formatToModernDisplay()}",
+                    value = "₿ ${
+                        (channel.inboundHtlcMaximumMsat?.let { MSat(it).floor() } ?: 0u).formatToModernDisplay()
+                    }",
                 )
                 ChannelDetailRow(
                     title = stringResource(R.string.lightning__inbound_htlc_min),