feat: Vendor pezkuwi-subxt and pezkuwi-zombienet-sdk into monorepo

- Add pezkuwi-subxt crates to vendor/pezkuwi-subxt
- Add pezkuwi-zombienet-sdk crates to vendor/pezkuwi-zombienet-sdk
- Convert git dependencies to path dependencies
- Add vendor crates to workspace members
- Remove test/example crates from vendor (not needed for SDK)
- Fix feature propagation issues detected by zepter
- Fix workspace inheritance for internal dependencies
- All 606 crates now in workspace
- All 6919 internal dependency links verified correct
- No git dependencies remaining

vendor/pezkuwi-zombienet-sdk/crates/orchestrator/src/utils.rs

@@ -0,0 +1,8 @@
+use serde::Deserializer;
+
+pub fn default_as_empty_vec<'de, D, T>(_deserializer: D) -> Result<Vec<T>, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    Ok(Vec::new())
+}