cleanup: drop two #[allow] attributes that were hiding real dead code

- ingestd/src/service.rs: top-of-file `#[allow(unused_imports)]`
    was masking genuinely unused `delete` and `patch` routing
    constructors in an axum import block. Removed the attribute,
    trimmed the imports to only `get` and `post` (what's actually
    used). Any future over-import now trips the unused_imports
    lint immediately instead of being silently allowed.

  - gateway/src/v1/truth.rs: `truth_router()` was a 4-line stub
    wrapping a single `/context` route — carried `#[allow(dead_code)]`
    because v1/mod.rs wires `get(truth::context)` directly onto its
    own router, bypassing this helper. Zero callers across the
    workspace. Deleted the function + allow + now-unused Router
    import. Left a breadcrumb comment pointing to the real wiring.

Workspace warnings: 0 (lib + tests). Each #[allow] removed raises
the bar on future code entering these modules — the linter now
catches the same classes of bugs at PR time.

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

crates/gateway/src/v1/truth.rs

@@ -1,12 +1,10 @@
-use axum::{routing::get, Router};
 use serde::Serialize;
 use truth::default_truth_store;
 
-#[allow(dead_code)]
+// Note: truth_router() was a stub wrapper around a single /context route
-pub fn truth_router() -> Router {
+// that nothing called — v1/mod.rs wires get(truth::context) directly
-    Router::new()
+// onto its own router. Removed 2026-04-24 along with its #[allow(dead_code)]
-        .route("/context", get(context))
+// attribute; the handler below is the real surface.
-}
 
 #[derive(Serialize)]
 pub struct ContextResponse {

crates/ingestd/src/service.rs

@@ -1,10 +1,9 @@
-#[allow(unused_imports)]
 use axum::{
     Json, Router,
     extract::{Multipart, Path, Query, State},
     http::{HeaderMap, StatusCode},
     response::IntoResponse,
-    routing::{delete, get, patch, post},
+    routing::{get, post},
 };
 use bytes::Bytes;
 use object_store::ObjectStore;