fix(macos): preserve modifier state in input events

[martona]

Description

Fix macOS keyboard event handling so modifier state is preserved reliably across keyboard and mouse input.

macOS input handling was reusing a mutable CGEventRef for keyboard events. That could leave stale event state behind and caused modifier combinations such as Shift+Enter or Cmd+Tab to be replayed inconsistently.

This change creates fresh keyboard events for each input update:

• Modifier keys use a fresh generic CGEventCreate(...) event with kCGEventFlagsChanged.
• Non-modifier keys use CGEventCreateKeyboardEvent(...) for key up/down events.
• The tracked modifier flags are applied to all keyboard events before posting.
• Mouse events also receive the tracked modifier flags so combinations such as Shift+Click are preserved.

Tested manually on macOS via Moonlight/Sunshine input replay:

• Releasing Shift no longer emits an extra key that was pressed before it; previously, it was prone to do that on occasion.
• Cmd+Tab app cycling works; previously Tab key-up could be lost while Cmd was held.
• Shift+Click preserves modifier state; previously modifier keys did not work with mouse clicks.

Screenshot

Issues Fixed or Closed

Roadmap Issues

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

[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

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