build(ios): enable iOS bazel targets on Bazel 9 and mac CI

.github/workflows/branch.yml

@@ -158,3 +158,30 @@ jobs:
         if: steps.filter.outputs.changed == 'true'
         working-directory: domains/games/apps/wordchains_ios
         run: swift test
+
+      - uses: bazel-contrib/setup-bazel@0.18.0
+        if: steps.filter.outputs.changed == 'true'
+        with:
+          bazelisk-cache: true
+          disk-cache: test-ios
+          repository-cache: true
+
+      - name: Build iOS app with bazel
+        if: steps.filter.outputs.changed == 'true'
+        run: |
+          bazel build //domains/games/apps/wordchains_ios:WordChains \
+            --ios_minimum_os=17.0 \
+            --apple_platform_type=ios
+
+      # swift.enable_testing is needed for @testable imports because the repo
+      # builds -c opt, where rules_swift disables testability by default.
+      # Without an explicit simulator device the test runner pairs an ancient
+      # device type (iPhone 6s Plus) with the latest iOS runtime and the
+      # simulator fails to boot.
+      - name: Run iOS unit tests with bazel
+        if: steps.filter.outputs.changed == 'true'
+        run: |
+          bazel test //domains/games/apps/wordchains_ios:WordChainsTests \
+            --ios_minimum_os=17.0 \
+            --features=swift.enable_testing \
+            --ios_simulator_device="iPhone 16"

.github/workflows/release-wordchains-ios.yml

@@ -143,11 +143,7 @@ jobs:
           disk-cache: release-wordchains-ios
           repository-cache: true
 
-      # rules_apple doesn't support Bazel 9 yet; pin to Bazel 8 LTS for iOS builds.
-      # Track: https://github.com/bazelbuild/rules_apple/issues
       - name: Build iOS app
-        env:
-          USE_BAZEL_VERSION: 8.2.1
         run: |
           bazel build //domains/games/apps/wordchains_ios:WordChains \
             --ios_minimum_os=17.0 \

domains/games/apps/wordchains_ios/BUILD.bazel

@@ -15,13 +15,14 @@ swift_library(
         ":word_graph_json",
     ],
     module_name = "WordChains",
-    tags = ["manual"],
-    target_compatible_with = ["@platforms//os:macos"],
+    target_compatible_with = ["@platforms//os:ios"],
 )
 
-# Tagged manual: rules_apple doesn't support Bazel 9 yet.
-# https://github.com/bazelbuild/rules_apple/issues/2863
-# Build with: USE_BAZEL_VERSION=8.2.1 bazel build //domains/games/apps/wordchains_ios:WordChains
+# The Apple bundling rules transition to an iOS target platform before
+# target_compatible_with is evaluated, so os:ios can't keep Linux CI off
+# them — Linux analysis fails resolving an Apple C++ toolchain instead of
+# skipping. Tag them manual; the test-ios job and the release workflow
+# request them by explicit label, which builds manual targets.
 ios_application(
     name = "WordChains",
     bundle_id = "com.muchq.wordchains",
@@ -35,7 +36,7 @@ ios_application(
         ":word_graph_json",
     ] + glob(["Sources/Resources/**"]),
     tags = ["manual"],
-    target_compatible_with = ["@platforms//os:macos"],
+    target_compatible_with = ["@platforms//os:ios"],
     visibility = ["//visibility:public"],
     deps = [":WordChainsLib"],
 )
@@ -44,11 +45,13 @@ swift_library(
     name = "WordChainsTestLib",
     testonly = True,
     srcs = glob(["Tests/**/*.swift"]),
-    tags = ["manual"],
-    target_compatible_with = ["@platforms//os:macos"],
+    target_compatible_with = ["@platforms//os:ios"],
     deps = [":WordChainsLib"],
 )
 
+# Unlike ios_application, the test rule stays in the host configuration
+# (only its deps transition to iOS), so it must be compatible with the
+# macOS host that runs the simulator.
 ios_unit_test(
     name = "WordChainsTests",
     minimum_os_version = "17.0",