feat: Add localizable search placeholder (fix #2382)

[TiEul]

This change allows for different strings to be used for each language on
the search placeholder.

Summary

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

• Bugfix
• Feature
• Code style update
• Refactor
• Docs
• Build-related changes
• Other, please describe:

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Does this PR introduce a breaking change? (check one)

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• No

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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)

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To avoid wasting your time, it's best to open a feature request issue first and wait for approval before working on it.

Other information:

#2382