docs: update CHANGELOG for v0.2.0

CHANGELOG.md

@@ -7,6 +7,18 @@ Format: [Keep a Changelog](https://keepachangelog.com/en/1.1.0/)
 
 ## [Unreleased]
 
+## [0.2.0] — 2026-04-24
+
+### Added
+- `nu node block <height>` — calls `nu_getBlock`, prints null if not found
+- `nu node account <address>` — calls `nu_getAccount`, displays balance in Shell and NU
+- `nu story show/node/list/pending` — wired to RPC (`nu_getStory`, `nu_getNode`, `nu_listStories`, `nu_listPendingVotes`)
+- `clap env` feature — `NU_RPC_URL` env variable support
+
+### Changed
+- `rpc::Client` params changed from object to **positional array** — matches nu-node sözleşmesi
+- `rpc::Client::new` auto-appends `/rpc` path suffix
+
 ## [0.1.0] — 2026-04-24
 
 ### Added