Update English Language Used on Kusion pages

## Enhancement
Per [Issue 1166 ](https://github.com/KusionStack/kusion/issues/1166), I am creating an issue to update the english grammar/language use on kusionstack.io.

I saw Issue 1166 through clotributor.dev and before going crazy I wanted to do a sample PR to see if the language updates I made fit with what you are desiring. If so and you would like me to, I can go further into the different pages at https://www.kusionstack.io/ and begin updating the language.

Start by reading Issue 1166 and reviewing the English language on the pages at kusionstack.io. Confirm the expected wording style with the proposed sample PR, then update the agreed pages and verify that their language matches the project’s expectations.

Written by the indexing model from the issue text.