fix(ci): update Rust version, cross-compile arm64 with cross, fix fail-fast

Dockerfile:
- Update FROM rust:1.86-bookworm → rust:1.94-bookworm to match rust-toolchain.toml
- Fix health check comment: /healthz → /health

release.yml:
- Add fail-fast: false so darwin jobs don't get cancelled when linux fails
- Replace manual gcc-aarch64 + openssl headers with taiki-e/cross for linux-arm64
- cross handles all system deps (OpenSSL, libc) in a pre-configured Docker image
- release job no longer waits for docker job (they're independent)

Cross.toml:
- Install protobuf-compiler in cross container (needed by tonic-build)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: easel

.github/workflows/release.yml

@@ -16,6 +16,7 @@ jobs:
   build:
     name: Build ${{ matrix.artifact }}
     strategy:
+      fail-fast: false
       matrix:
         include:
           - os: ubuntu-latest
@@ -54,16 +55,14 @@ jobs:
         if: runner.os == 'macOS'
         run: brew install protobuf
 
-      - name: Install cross-compilation tools (Linux arm64)
+      - name: Install cross (for Linux arm64)
         if: matrix.cross
-        run: |
-          sudo apt-get update
-          sudo apt-get install -y gcc-aarch64-linux-gnu
+        uses: taiki-e/install-action@v2
+        with:
+          tool: cross
 
       - name: Build
-        env:
-          CARGO_TARGET_AARCH64_UNKNOWN_LINUX_GNU_LINKER: ${{ matrix.cross && 'aarch64-linux-gnu-gcc' || '' }}
-        run: cargo build --release -p axon-cli --target ${{ matrix.target }}
+        run: ${{ matrix.cross && 'cross' || 'cargo' }} build --release -p axon-cli --target ${{ matrix.target }}
 
       - name: Rename binary
         run: cp target/${{ matrix.target }}/release/axon ${{ matrix.artifact }}
@@ -111,7 +110,7 @@ jobs:
 
   release:
     name: Create Release
-    needs: [build, docker]
+    needs: build
     runs-on: ubuntu-latest
     steps:
       - uses: actions/download-artifact@v4

Cross.toml

@@ -0,0 +1,4 @@
+[target.aarch64-unknown-linux-gnu]
+pre-build = [
+    "apt-get update && apt-get install -y --no-install-recommends protobuf-compiler"
+]

Dockerfile

@@ -5,11 +5,11 @@
 #
 # The binary is `axon` (from crates/axon-cli, the unified binary).
 # Default HTTP port is 4170. gRPC is opt-in via --grpc-port.
-# Health check: GET /healthz
+# Health check: GET /health
 
 # ── Stage 1: Builder ──────────────────────────────────────────────────────────
 
-FROM rust:1.86-bookworm AS builder
+FROM rust:1.94-bookworm AS builder
 
 # protobuf-compiler is required by tonic-build for gRPC code generation.
 RUN apt-get update && apt-get install -y --no-install-recommends \