fix: upgrade Rust to 1.85 for edition2024 support

base64ct 1.8.1 and other dependencies in Cargo.lock require
Rust edition2024, which is only supported in Rust 1.85+.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: SamoraDC

Dockerfile

@@ -6,7 +6,7 @@
 # ============================================================================
 # Stage 1: Rust Builder with ONNX Runtime
 # ============================================================================
-FROM rust:1.83-slim-bookworm AS rust-builder
+FROM rust:1.85-slim-bookworm AS rust-builder
 
 # Install build dependencies + ONNX Runtime
 RUN apt-get update && apt-get install -y \