chore(clippy): silence three v1.1.0-foundation lints

- sdk/bridge.rs: drop #[must_use] on the bridge fns — `Dynamic` and
    `serde_json::Value` are both #[must_use] already; the wrapper
    attribute is double-must-use noise.
  - api.rs IntoResponse: hoist `use ApiError as E;` above the early
    Overloaded branch so `E::Exec(...)` works in the if-let too
    (clippy::items_after_statements).
  - gate.rs test: bind the returned permit with `let _ =` so the
    OwnedSemaphorePermit doesn't trip unused-must-use.

No behaviour change. Caught by `cargo clippy --all-targets
--all-features -- -D warnings`.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

crates/orchestrator-core/src/api.rs

@@ -424,7 +424,8 @@ impl IntoResponse for ApiError {
         // header (Retry-After), so it short-circuits the (status, body)
         // reduction below. Axum's tuple builder makes per-arm header
         // injection awkward otherwise.
-        if let ApiError::Exec(ExecError::Overloaded { retry_after_secs }) = &self {
+        use ApiError as E;
+        if let E::Exec(ExecError::Overloaded { retry_after_secs }) = &self {
             let retry = retry_after_secs.to_string();
             let body = Json(serde_json::json!({ "error": self.to_string() }));
             return (
@@ -435,7 +436,6 @@ impl IntoResponse for ApiError {
                 .into_response();
         }
 
-        use ApiError as E;
         let (status, message) = match &self {
             E::NotFound(_) => (StatusCode::NOT_FOUND, self.to_string()),
             E::BadRequest(_) => (StatusCode::BAD_REQUEST, self.to_string()),

crates/orchestrator-core/src/gate.rs

@@ -142,7 +142,8 @@ mod tests {
         {
             let _p = gate.try_acquire().expect("first permit available");
         }
-        gate.try_acquire()
+        let _ = gate
+            .try_acquire()
             .expect("slot must be returned after permit drops");
     }