fix(tray): prevent crashes and keep icon states

[Nonary]

Description

This fixes the system tray to keep persistent state on statuses of the stream and also protects calling threads from being deadlocked in case there is an issue with the notification itself.

Screenshot

Issues Fixed or Closed

• Fixes Cannot open context menu from tray icon while streaming and no "playing" icon #4021
• Fixes Indefinite hang with no notification manager #4031

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

See analysis details on SonarQube Cloud

[Nonary]

There is actually a deeper issue with the tray, it intermittently breaks notifications and the menus stop working. Might be a bit before I figure out what specifically causes that. I thought it was dangling pointers at first, but it doesn't appear to be the case.

All I know is if you happen to use the modern notification view, it will sometimes break the notifications for Sunshine entirely until you restart the service.