Enhance macOS provisioning profile handling in build scripts and documentation

This commit updates the check_signing_identities.sh script to search for provisioning profiles in multiple common directories, improving the detection process. Additionally, the README_MAS.md is updated to clarify where provisioning profiles are stored in newer Xcode versions and provides guidance on locating the correct profile for Mac App Store builds. This enhances the overall usability and clarity for developers working with macOS builds.

build_tools/macos/README_MAS.md

@@ -103,9 +103,32 @@ In Apple Developer → **Profiles** → **+**:
 - Select the **Apple Distribution** certificate
 - Generate + Download
 
-Install it by double-clicking it, or place it under:
+### Where the `.provisionprofile` ends up (newer Xcode/macOS)
 
-`~/Library/MobileDevice/Provisioning Profiles/`
+Recent Xcode versions store “downloaded manual profiles” under:
+
+- `~/Library/Developer/Xcode/UserData/Provisioning Profiles/`
+
+Older tooling sometimes used:
+
+- `~/Library/MobileDevice/Provisioning Profiles/`
+
+This repo’s MAS build script does **not** require the profile to be in a specific folder — you can pass the path directly.
+
+To locate and pick the right profile, use:
+
+```bash
+./build_tools/macos/find_mas_provisioning_profile.sh --bundle-id com.dryark.strawberry
+```
+
+### (Optional) Copy to the legacy folder
+
+If some other tools expect the legacy folder, you can copy it there:
+
+```bash
+mkdir -p "$HOME/Library/MobileDevice/Provisioning Profiles"
+cp -f "/path/to/profile.provisionprofile" "$HOME/Library/MobileDevice/Provisioning Profiles/"
+```
 
 ---