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/executor-core/src/sdk/bridge.rs

@@ -14,7 +14,6 @@ use serde_json::Value as Json;
 /// pushing into a script's scope. Numbers prefer the narrowest type
 /// (`i64` over `f64`); anything that can't round-trip falls back to a
 /// string so the script always sees a defined value.
-#[must_use]
 pub fn json_to_dynamic(value: Json) -> Dynamic {
     match value {
         Json::Null => Dynamic::UNIT,
@@ -48,7 +47,6 @@ pub fn json_to_dynamic(value: Json) -> Dynamic {
 /// types (timestamps, user-registered modules) fall back to their
 /// `Display` form so they appear as strings in JSON output rather than
 /// failing the response build.
-#[must_use]
 pub fn dynamic_to_json(value: &Dynamic) -> Json {
     if value.is_unit() {
         return Json::Null;