Let the probe's clock be its proof, not disable_cpu_ep_fallback

The strict flag refused the Hexagon over the ten quantise/dequantise
nodes at the graph's edges that QNN declines by policy, which cost
microseconds. A provider that hands real work to the CPU is slower than
the CPU floor and the timing already rejects it; the tablet measured
2.3 ms on the NPU against a 29.7 ms floor.

core/dr-inference-engine/src/lib.rs

@@ -253,7 +253,7 @@ fn acquire(role: Role, form: Form, bytes: &Arc<[u8]>) -> Result<Acquired, Error>
 
     // Built outside the registry lock: a TensorRT engine load is long enough
     // that another role's acquire should not wait on it.
-    let session = session::build(rung, role, bytes, &cfg, false)?;
+    let session = session::build(rung, role, bytes, &cfg)?;
     log::debug!("inference: {role:?} loaded on {}", rung.label());
     let entry = Arc::new(Loaded {
         rung,