feat(i18n): src/content/learn/escape-hatches.md from English to Vietnamese

[KotonoSora]

🇻🇳 Vietnamese Translation: Escape Hatches

Hi! I'm contributing as a volunteer translator for vi.react.dev, and this PR adds the Vietnamese translation for the "Escape Hatches" lesson.

What's included

• Vietnamese translation of escape-hatches.md
• Preserved all code examples and markdown formatting
• Kept terminology consistent with existing translations

Changes

• ✅ Fully translated the guide covering how to use React escape hatches to interact with external systems, refs, Effects, and custom Hooks
• ✅ Maintained code blocks, links, Sandpack components and Challenge/Solution sections
• ✅ Verified all internal links and formatting render correctly

Looking forward to contributing more translations to the project! 🚀

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Tóm tắt những gì đã được dịch:

Tiêu đề và phần Intro:
"Escape Hatches" → "Lối Thoát (Escape Hatches)"

Các phần chính:

• "Referencing values with refs" → "Nhớ giá trị với refs"
• "Manipulating the DOM with refs" → "Thao tác DOM với refs"
• "Synchronizing with Effects" → "Đồng bộ hóa với Effects"
• "You Might Not Need An Effect" → "Có thể bạn không cần một Effect"
• "Lifecycle of reactive effects" → "Lifecycle của reactive effects"
• "Separating events from Effects" → "Tách biệt events khỏi Effects"
• "Removing Effect dependencies" → "Loại bỏ Effect dependencies"
• "Reusing logic with custom Hooks" → "Tái sử dụng logic với custom Hooks"
• "What's next?" → "Tiếp theo là gì?"