Exercise 2: Confirming JavaScript's String Behavior — Possible Solution
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NODE REPL SESSION
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> '水のページ'.length
5
> '水のページ'.slice(0, 3)
'水のペ'

WHAT THIS CONFIRMS
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Per this chapter, JavaScript strings are UTF-16 code unit sequences,
and common kanji characters like 水 fall within the Basic
Multilingual Plane, each represented as exactly one UTF-16 code
unit. This means .length correctly reports 5 (five real characters,
not a byte count), and .slice(0, 3) correctly cuts at a real
character boundary rather than corrupting a multi-unit character
mid-way through.

WHY THIS WORKS AS AN ANSWER
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It correctly demonstrates real JavaScript string behavior on a
kanji-containing string, confirming the chapter's own claim that
Astro inherits the exact same safe string model Next.js already
relied on, with no new risk introduced.