Content Classification: Make character count locale-aware

[t-hamano]

Description

Content classification requires more than 150 words to be enabled. However, CJK languages like Japanese and Chinese do not use spaces between words. Consequently, this feature cannot be utilized even with sufficient content.

We should adopt a locale-aware approach rather than hard-coding the words. So, as the word count type, we should use the translated text.

https://github.com/WordPress/gutenberg/blob/1ecc3d2fe9c819af35ef312563805bc16a103036/packages/block-library/src/post-time-to-read/edit.js#L51-L61

ai/src/experiments/content-classification/components/SuggestionPanel.tsx

Line 77 in 396fcc3

'Add more content to enable AI suggestions (approximately 150 words).',

This text should also change depending on whether it is counted by words or characters.

Add more content to enable AI suggestions (approximately 150 words).
Add more content to enable AI suggestions (approximately 150 characters).

Step-by-step reproduction instructions

• Change the site language to Japanese.
• Open a post.
• Copy the following Japanese text multiple times to create content: こんにちは。
• Confirm that the Suggest Categories button remains disabled.

Screenshots, screen recording, code snippet

Environment info

No response

Please confirm that you have searched existing issues in the repo.

• Yes

Please confirm that you have tested with all plugins deactivated except the AI plugin.

• Yes

Please confirm which theme type you used for testing.

• Block
• Classic
• Hybrid (e.g. classic with theme.json)
• Not sure