ci: pin docker image to 1.92

Author: evansims

.github/dependabot.yml

@@ -59,6 +59,10 @@ updates:
     commit-message:
       prefix: "docker"
       include: "scope"
+    ignore:
+      # Rust version is pinned to match rust-toolchain.toml (1.92)
+      # Update manually when upgrading the project's Rust version
+      - dependency-name: "rust"
     groups:
       docker-images:
         patterns:

Dockerfile

@@ -12,7 +12,7 @@
 # =============================================================================
 # Stage 1: Builder
 # =============================================================================
-FROM rust:1.93-bookworm AS builder
+FROM rust:1.92-bookworm AS builder
 
 # Install protobuf compiler and well-known types (required for gRPC code generation)
 RUN apt-get update && apt-get install -y --no-install-recommends \