fix(cua-driver): eliminate duplicate Swift bridge symbols

.github/workflows/ci-swift-linker.yml

@@ -0,0 +1,45 @@
+name: "CI: macOS Swift linker"
+
+on:
+  pull_request:
+    paths:
+      - "libs/cua-driver/rust/**"
+      - "scripts/ci/macos/test-swift-linker-symbols.sh"
+      - ".github/workflows/ci-swift-linker.yml"
+  push:
+    branches: [main]
+    paths:
+      - "libs/cua-driver/rust/**"
+      - "scripts/ci/macos/test-swift-linker-symbols.sh"
+      - ".github/workflows/ci-swift-linker.yml"
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: swift-linker-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  link:
+    name: Fresh macOS link without duplicate symbols
+    runs-on: macos-latest
+    timeout-minutes: 20
+    steps:
+      - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5
+      - uses: dtolnay/rust-toolchain@stable
+      - name: Verify native linker output
+        env:
+          TMPDIR: ${{ runner.temp }}/
+        run: bash scripts/ci/macos/test-swift-linker-symbols.sh
+      - name: Preserve linker evidence
+        if: always()
+        uses: actions/upload-artifact@65c4c4a1ddee5b72f698fdd19549f0f0fb45cf08
+        with:
+          name: swift-linker-evidence
+          if-no-files-found: error
+          path: |
+            ${{ runner.temp }}/cua-swift-linker.*/environment.txt
+            ${{ runner.temp }}/cua-swift-linker.*/build.log
+            ${{ runner.temp }}/cua-swift-linker.*/duplicate-symbols.txt

libs/cua-driver/rust/crates/platform-macos/Cargo.toml

@@ -60,7 +60,7 @@ objc2-quartz-core = { version = "0.2", features = ["CALayer"] }
 # ffmpeg subprocess on macOS. `macos_15_0` enables the `SCRecordingOutput`
 # convenience that finalises an mp4 in-process, removing the per-binary
 # Screen Recording TCC prompt that subprocess capture would otherwise trip.
-screencapturekit = { version = "6", features = ["macos_15_0"] }
+screencapturekit = { version = "8.0.1", features = ["macos_15_0"] }
 security-framework = { version = "3.7.0", default-features = false, features = ["OSX_10_15"] }
 zeroize = { workspace = true }
 getrandom = { workspace = true }

scripts/ci/macos/test-swift-linker-symbols.sh

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+if [[ "$(uname -s)" != Darwin ]]; then
+  echo "This regression check requires a native macOS linker." >&2
+  exit 2
+fi
+
+REPO_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/../../.." && pwd)"
+ARTIFACT_DIR="$(mktemp -d "${TMPDIR:-/tmp}/cua-swift-linker.XXXXXX")"
+export CARGO_TARGET_DIR="${ARTIFACT_DIR}/target"
+export CARGO_TERM_COLOR=never
+export RUSTFLAGS="${RUSTFLAGS:+${RUSTFLAGS} }-W linker-messages"
+unset CARGO_ENCODED_RUSTFLAGS
+
+printf 'Evidence: %s\n' "${ARTIFACT_DIR}"
+{
+  git -C "${REPO_ROOT}" rev-parse HEAD
+  rustc --version
+  cargo --version
+  xcrun swift --version
+  sw_vers
+} > "${ARTIFACT_DIR}/environment.txt" 2>&1
+
+set +e
+cargo build --manifest-path "${REPO_ROOT}/libs/cua-driver/rust/Cargo.toml" \
+  --release --locked -p cua-driver 2>&1 | tee "${ARTIFACT_DIR}/build.log"
+BUILD_STATUSES=("${PIPESTATUS[@]}")
+set -e
+
+if [[ "${BUILD_STATUSES[0]}" != 0 || "${BUILD_STATUSES[1]}" != 0 ]]; then
+  printf 'FAIL: native build or evidence capture failed (%s).\n' "${BUILD_STATUSES[*]}" >&2
+  exit 1
+fi
+
+if grep -iE 'duplicate symbols?([[:space:]]|:)' "${ARTIFACT_DIR}/build.log" \
+    > "${ARTIFACT_DIR}/duplicate-symbols.txt"; then
+  echo "FAIL: successful native build emitted duplicate-symbol linker diagnostics." >&2
+  exit 1
+fi
+
+echo "PASS: fresh native build succeeded without duplicate-symbol linker diagnostics."