Add missing model_picker fields to Rust test fixtures

The 1.0.46 update added `model_picker_category` and
`model_picker_price_category` fields to the `Model` type. Update the
Rust test fixtures in lib.rs and tests/e2e/client.rs to initialize these
new fields so clippy passes.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: tclem

rust/src/lib.rs

@@ -2440,6 +2440,8 @@ mod tests {
             },
             default_reasoning_effort: None,
             id: "byok-gpt-4".into(),
+            model_picker_category: None,
+            model_picker_price_category: None,
             name: "BYOK GPT-4".into(),
             policy: None,
             supported_reasoning_efforts: Vec::new(),
@@ -2483,6 +2485,8 @@ mod tests {
             },
             default_reasoning_effort: None,
             id: "single-flight-model".into(),
+            model_picker_category: None,
+            model_picker_price_category: None,
             name: "Single Flight Model".into(),
             policy: None,
             supported_reasoning_efforts: Vec::new(),

rust/tests/e2e/client.rs

@@ -269,6 +269,8 @@ impl ListModelsHandler for CountingModelsHandler {
             },
             default_reasoning_effort: None,
             id: "custom-handler-model".to_string(),
+            model_picker_category: None,
+            model_picker_price_category: None,
             name: "Custom Handler Model".to_string(),
             policy: None,
             supported_reasoning_efforts: Vec::new(),