Cocoa: Apple native-client update

[melekr]

Integrate Cocoa 2.2.0 across Unity's Apple native clients

Summary

Update Backtrace Unity to backtrace-cocoa ver. 2.2.0, fix macOS native pending-report isolation, and use one managed interop/lifecycle implementation for macOS and iOS.

Why

The previous macOS integration used PLCrashReporter's default pending-report namespace, which Unity also inspects during startup. Backtrace reports could be consumed before the SDK initialized. The affected Unity 6000.3 reproduction could also crash during relaunch in CrashReporting::CrashReporter::CheckPendingNativeCrash.

The old macOS plugin additionally depended on symlinks in a nested versioned framework. The new plugin is a flat, self-contained universal bundle.

The iOS update consumes the dedicated device/simulator Cocoa XCFrameworks and brings the managed/native boundary under the same explicit allocation and lifecycle rules, while preserving the existing iOS pending-report path and OOM Light behavior.

Implementation

Shared managed Apple integration

• Use AppleNativeBridge, AppleNativeSession, and AppleNativeClient. Retain the platform-specific factories and small macOS/iOS adapters.
• Require ABI V3, explicit UTF-8 argument allocations, Cdecl, and one-byte C Boolean marshalling.
• Propagate ReportPerMin, including 0 for unlimited native admission.
• Release native GetAttributes memory through native FreeAttributes, including failure paths; do not free native-owned allocations with the managed allocator.
• Initialize native capture independently of the managed offline database.
• Do not construct a cached inert wrapper when capture is initially disabled.
• Retain an existing owner across repeated Refresh() calls.
• Coordinate admitted operations and shutdown without replacing a potentially installed process-wide fatal handler.
• Preserve watchdog heartbeat/ANR behavior and restore crash classification after a native ANR attempt.

macOS

• Replace the old nested framework with the approved flat arm64/x86_64 BacktraceMacUnity.bundle.
• Retain the BTUnity-prefixed PLCrashReporter implementation, Foundation-derived private payload base, and cooperative capture lease.
• Keep the capture lease for the process lifetime once handler installation may have occurred. A second cooperating same-ID process does not take over that native capture slot; managed reporting remains independent.
• Does NOT add a runtime shared-cache rename/restore callback or automatic legacy migration. Existing old shared-cache payloads require the separate controlled prelaunch recovery procedure when applicable.

iOS

• Replace both iOS XCFramework trees with the approved dedicated device/simulator archive, preserving the native bytes, importer GUIDs, resources and included debug symbols.
• Add a result-returning local V3 Objective-C++ bridge and retain the previously shipped void startup export for older callers.
• Preserve the existing PLCrashReporter storage path and OOM Light mode; do not copy the macOS path/lease policy to iOS.
• Allocate and free returned attribute entries safely, including partial allocation failure.
• Retain the reporter once process-wide handler installation may have begun. Native shutdown runs outside the bridge state monitor.
• Compile only the bridge source with -fobjc-arc -fobjc-exceptions -fno-autolink.

iOS Xcode integration

• Retain one required postprocessor. Link the dynamic Backtrace framework to UnityFramework and embed it in the application.
• Use SDK-specific CrashReporter headers without linking or embedding a second static PLCrashReporter copy.
• Normalize only SDK-owned link/embed entries on repeated processing.
• Preserve host runpaths, including quoted paths and app-only configurations.
• Package static-runtime privacy declarations and attribution separately, without modifying the host application's privacy manifest.
• Resolve attribution resources from Assets or PackageCache using the preserved source-asset GUID.
• Reject an iOS app minimum below 15.0 instead of silently raising it.

Packaging, tooling and tests

• Preserve existing native importer identities and signed source bytes. The Mac importer disables Editor loading and preloading as part of this integration.
• Keep direct Apple native-artifact and package validation in CI.
• Retain existing platform coverage and add real macOS Mono/IL2CPP builds and iOS IL2CPP device/ARM64 Simulator exports followed by Xcode compilation.
• Add shared-runtime and iOS Editor integration regression tests. Run the Editor tests synchronously with the active iOS target before export in both existing modern iOS CI lanes, retain XML/logs even after failure and require all named cases to pass using the existing result checker.

ref: BT-7562
ref: BT-7522