fix: fix the problem that userAgentData.brands might be undefined

[Rossonero]

Type of PR: bugfix

PR checklist:

Fixes #2046

Overview of change:

This PR fixes the issue that navigator.userAgentData.brands is sometimes undefined in some environments. The root causes are browser compatibility (e.g., Firefox, Safari do not support navigator.userAgentData API) and privacy policy restrictions (e.g., strict privacy mode in Chromium-based browsers disables the API).

The fix implements a compatible solution:

1. First check if navigator.userAgentData and navigator.userAgentData.brands exist; if they do, use the standard API as before.

2. If not, degrade to parse the traditional navigator.userAgent string to extract browser brand and version information, ensuring consistent return format and avoiding code errors.

3. Filter the placeholder brand Not/A)Brand in brands array (added by browsers for anti-fingerprinting) to ensure the returned data is valid and usable.

This change is backward-compatible, does not affect existing functionality in supported browsers, and effectively resolves the undefined error in unsupported environments or privacy-restricted scenarios.

Is there anything you'd like reviewers to focus on?

1. Whether the compatible logic of navigator.userAgentData and navigator.userAgent is complete, and if there are any edge cases (e.g., special browser userAgent strings) not covered.

2. Whether the return format of the browser information is consistent with the original design, to avoid affecting subsequent business logic that depends on this data.

3. Whether the filtering logic of Not/A)Brand is reasonable and does not filter out valid brand information.

[Copilot]

Pull request overview

This PR fixes a runtime error where navigator.userAgentData.brands could be undefined in certain browsers or privacy-restricted environments, causing the isChromiumBased() function to fail.

Changes:

• Added explicit check for navigator.userAgentData.brands array existence before attempting to access it
• Prevents TypeError when brands property is undefined due to browser compatibility or privacy settings

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