Fix #2699: Prevent trashcan from being obscured by scrollbar

[LuciferDono]

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Description

When users have "Always show scrollbars" enabled in their OS settings, the trashcan (delete) and reset buttons on assigned site list rows are partly hidden behind the visible scrollbar.

Root cause: .truncate-text used inline-size: calc(100vw - 100px), which bases the width on the full viewport — including the area consumed by the scrollbar. This forced the text span to a fixed width that overflows the flex container when a scrollbar is present, pushing the action buttons behind it.

Fix: Replace the fixed calc() width with min-inline-size: 0, which is the standard CSS fix for allowing flex items to shrink below their content size. The parent <td> already uses display: flex and .menu-text already has flex: 1, so the text span now naturally fills only the remaining space after the favicon and buttons — regardless of whether a scrollbar is visible.

Type of change

• Bug fix
• New feature
• Major change

Fixes #2699

[bakulf]

Can you please attach a screenshot before and after? Thanks!