build: bump version to 0.3.0 for breaking API changes

Breaking changes in this release:
- DelegateInterface::process: attested → origin: Option<MessageOrigin>
- ApplicationMessage: removed app field, new() takes only payload
- New public type: MessageOrigin enum

Author: iduartgomez

rust/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "freenet-stdlib"
-version = "0.2.2"
+version = "0.3.0"
 edition = "2021"
 rust-version = "1.80"
 publish = true