feat: macOS support

[martona]

Description

As requested, here's the macOS support PR, and a windows+macoOS power-management subfeature aimed at keeping the display awake.

• macOS display enumeration works for online displays.
• Active display info works: current mode, resolution, refresh rate, scale, origin, main-display status, friendly name, EDID when available.
• Stable macOS device_id generation works, with EDID/IOKit metadata first and CoreGraphics fallback.
• getDisplayName() returns the numeric CGDirectDisplayID capture selector Sunshine needs.
• verify_only display configuration works on macOS.
• Resolution/refresh changes work for already-active displays, with persistence and revert.
• New cross-platform display power API exists: wake request plus scoped keep-awake guard.
• Windows gets equivalent display power API over SetThreadExecutionState.

Does not work:

• activating inactive displays
• enumerating disconnected/remembered displays the way Windows can
• topology mutation: no reliable public equivalent for enable/disable paths, EnsureActive, EnsurePrimary, or EnsureOnlyDisplay
• HDR mutation

So in summary, it's useful from day one when it gets integrated into Sunshine (conform to capture resolution, refresh rate, etc) with cross-platform semantics. It is not a 1:1 feature-complete Windows-equivalent implementation because macOS public display APIs do not expose the same topology, inactive-display, and HDR controls.

Screenshot

Issues Fixed or Closed

Roadmap Issues

• Resolves: libdisplaydevice: macOS support roadmap#57 (partially)

Type of Change

• feat: New feature (non-breaking change which adds functionality)
• fix: Bug fix (non-breaking change which fixes an issue)
• docs: Documentation only changes
• style: Changes that do not affect the meaning of the code (white-space, formatting, missing semicolons, etc.)
• refactor: Code change that neither fixes a bug nor adds a feature
• perf: Code change that improves performance
• test: Adding missing tests or correcting existing tests
• build: Changes that affect the build system or external dependencies
• ci: Changes to CI configuration files and scripts
• chore: Other changes that don't modify src or test files
• revert: Reverts a previous commit
• BREAKING CHANGE: Introduces a breaking change (can be combined with any type above)

Checklist

• Code follows the style guidelines of this project
• Code has been self-reviewed
• Code has been commented, particularly in hard-to-understand areas
• Code docstring/documentation-blocks for new or existing methods/components have been added or updated
• Unit tests have been added or updated for any new or modified functionality

AI Usage

• None: No AI tools were used in creating this PR
• Light: AI provided minor assistance (formatting, simple suggestions)
• Moderate: AI helped with code generation or debugging specific parts
• Heavy: AI generated most or all of the code changes

AI was heavily used, especially for tests; all code has been reviewed before committing.

[CLAassistant]

All committers have signed the CLA.

[ReenigneArcher]

This is awesome, thank you! I didn't test any of this, but the code structure seems generally good and follows the existing patterns in the project.

Could you fix the reported sonar issues and duplication? I normally point the AI to a sonar mcp server to do this, but that may not work if you don't own the project in sonar. I think it will work if you give it the link directly (https://sonarcloud.io/project/issues?id=LizardByte_libdisplaydevice&pullRequest=276&issueStatuses=OPEN,CONFIRMED&sinceLeakPeriod=true)... if it's too much trouble, I could also take care of that.

[codecov]

Codecov Report

❌ Patch coverage is 51.89753% with 507 lines in your changes missing coverage. Please review.
✅ Project coverage is 80.17%. Comparing base (3d7e7ca) to head (9274aba).
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
src/macos/mac_api_layer.cpp	32.76%	193 Missing and 45 partials ⚠️
src/macos/settings_manager_apply.cpp	48.21%	21 Missing and 37 partials ⚠️
src/macos/mac_display_device_modes.cpp	41.42%	10 Missing and 31 partials ⚠️
src/macos/settings_manager_revert.cpp	33.33%	14 Missing and 20 partials ⚠️
src/macos/settings_utils.cpp	64.36%	9 Missing and 22 partials ⚠️
src/macos/mac_display_device_general.cpp	55.10%	3 Missing and 19 partials ⚠️
src/windows/win_api_layer.cpp	0.00%	15 Missing and 3 partials ⚠️
src/macos/mac_display_device_topology.cpp	66.66%	1 Missing and 15 partials ⚠️
src/macos/display_power.cpp	73.07%	3 Missing and 11 partials ⚠️
src/macos/persistent_state.cpp	64.51%	6 Missing and 5 partials ⚠️
... and 8 more

Additional details and impacted files

@@             Coverage Diff             @@
##           master     #276       +/-   ##
===========================================
- Coverage   93.10%   80.17%   -12.93%     
===========================================
  Files          36       59       +23     
  Lines        2379     3370      +991     
  Branches     1123     1534      +411     
===========================================
+ Hits         2215     2702      +487     
- Misses         56      333      +277     
- Partials      108      335      +227     

Flag	Coverage Δ
Linux	93.39% <100.00%> (ø)
Windows-AMD64	91.11% <80.61%> (-0.62%)	⬇️
Windows-ARM64	67.04% <63.47%> (-0.23%)	⬇️
macOS	57.83% <48.94%> (-17.33%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...ude/display_device/detail/persistent_state_utils.h	100.00% <100.00%> (ø)
...n/include/display_device/display_power_interface.h	100.00% <100.00%> (ø)
...nclude/display_device/settings_manager_interface.h	100.00% <ø> (ø)
src/common/include/display_device/types.h	100.00% <100.00%> (ø)
...ude/display_device/macos/mac_api_layer_interface.h	100.00% <100.00%> (ø)
...isplay_device/macos/mac_display_device_interface.h	100.00% <100.00%> (ø)
src/macos/json.cpp	100.00% <100.00%> (ø)
src/macos/mac_api_utils.cpp	100.00% <100.00%> (ø)
src/windows/display_power.cpp	100.00% <100.00%> (ø)
...e/display_device/windows/win_api_layer_interface.h	100.00% <ø> (ø)
... and 19 more

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud