fix: changed topics/keywords to topic/keywords

[Riddhimaan-Senapati]

Summary

The metadata with key "topic/keywords" is probably accepted and saved by the backend, but the UI won't show the value because it uses a map of metadata keys to show:

dify/web/hooks/use-metadata.ts

Line 68 in 1f38d48

'topics/keywords': { label: t(${fieldPrefix}.webPage.topicsKeywords) },
Based on the file linked in the docs: https://github.com/langgenius/dify/blob/main/api/services/dataset_service.py#L475
The correct value should probably be "topic/keywords"

The backend seems to run validation on the accepted values for doc_type https://github.com/langgenius/dify/blob/main/api/controllers/service_api/dataset/document.py#L75

BUT it allows any Dictionary-Like object for the doc_metadata https://github.com/langgenius/dify/blob/main/api/controllers/service_api/dataset/document.py#L79

It should validate the object keys based on the values in dataset_service.py https://github.com/langgenius/dify/blob/main/api/services/dataset_service.py#L476

The UI hook should be updated to target the correct key "topic/keywords"

dify/web/hooks/use-metadata.ts

Line 68 in 1f38d48

'topics/keywords': { label: t(${fieldPrefix}.webPage.topicsKeywords) },
Along with the translation key

dify/web/i18n/en-US/dataset-documents.ts

Line 136 in 1f38d48

topicsKeywords: 'Topics/Keywords',

So I updated these files and the corresponding translations to use topic/Keywords or topicKeywords

Fixes #13502

Screenshots

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Checklist

Important

Please review the checklist below before submitting your pull request.

• This change requires a documentation update, included: Dify Document
• I understand that this PR may be closed in case there was no previous discussion or issues. (This doesn't apply to typos!)
• I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• I've updated the documentation accordingly.
• I ran dev/reformat(backend) and cd web && npx lint-staged(frontend) to appease the lint gods