Add changelog fragment for FromJSON TxOut

Author: Jimbo4350

.changes/20260420_cardano_api_fromjson_experimental_txout.yml

@@ -0,0 +1,12 @@
+project: cardano-api
+pr: 1179
+kind:
+  - feature
+description: |
+  Add FromJSON instances for the new experimental TxOut type, matching
+  the JSON format produced by the corresponding ToJSON instances. Inline
+  datums are parsed from inlineDatumRaw with hash validation against
+  inlineDatumhash. Reference scripts are parsed via the existing
+  FromJSON ScriptInAnyLang instance and converted to ledger scripts.
+  Supplemental datums are deliberately unsupported since the ledger
+  TxOut does not carry them.