refactor(tauri): Webview traits

[lucasfernog]

What kind of change does this PR introduce? (check at least one)

• Bugfix
• Feature
• New Binding Issue #___
• Code style update
• Refactor
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The PR fulfills these requirements:

• When resolving a specific issue, it's referenced in the PR's title (e.g. fix: #xxx[,#xxx], where "xxx" is the issue number)
• A change file is added if any packages will require a version bump due to this PR per the instructions in the readme.

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Other information:

This PR changes the Tauri integration with webview to use traits instead of direct webview_official usage. This simplifies the future implementation of wry.

[wusyong]

LGTM. But traits method might be different when introducing wry as a dependency.