fix(ui): resolve back button redirect loop on execution pages

[mohitjeswani01]

✨ Description

This PR resolves a navigation issue where users were trapped in a redirect loop when using the browser's Back button from an execution detail page.

Previously, navigating back would land users on an intermediate “untabbed” execution URL, which immediately redirected forward again — effectively trapping the user.

Key changes include:

• Router-level redirection by moving default tab logic from the component onMounted hook to a beforeEnter guard in routes.js.
• History management using replace: true during the initial redirect so the base execution URL (without a tab) is overwritten in browser history, allowing a single Back click to return to the Execution List.
• Dead code cleanup by removing the unused router instance and useRouter import in useExecutionRoot.ts to satisfy ESLint.

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🔗 Related Issue

Closes #14285

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🎨 Frontend Checklist

• Code builds without errors (npm run build)
• All existing E2E tests pass (npm run test:e2e)
• Screenshots or video recordings attached showing the UI changes
  (See attached kestra_back_button_routefix.mp4)

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📝 Additional Notes

The fix was verified locally by checking the browser history stack.

Previously, the stack recorded an intermediate “untabbed” URL which triggered a forward redirect upon back-navigation. The new implementation ensures the history stack remains clean.

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demo

kestra.button.fix.-.Made.with.Clipchamp.mp4

[MilosPaunovic]

Can you resolve the merge conflict here @mohitjeswani01?

[mohitjeswani01]

Hi @MilosPaunovic, I have resolved the merge conflicts in routes.js

[mohitjeswani01]

hi @MilosPaunovic do i need to make any changes in this ?

[MilosPaunovic]

Hi @mohitjeswani01,

This pull request will be reviewed at our earliest convenience.

Thanks for all the efforts so far! 🍀