chore: add changeset for tx fee fix

Author: fghdotio

.changeset/kind-hotels-care.md

@@ -0,0 +1,7 @@
+---
+'@rgbpp-sdk/ckb': patch
+---
+
+fix: ensure sufficient capacity when deducting tx fee from last output
+
+Fix capacity validation when deducting transaction fees from the last output to prevent insufficient capacity errors.