fix: site example(Search Highlighting) range

[WindRunnerMax]

Description
When I was testing the 'decorations' feature on the official website (search-highlighting), I noticed that there were some issues with supporting content that had been split into multiple formats.

Issue
none

Example
When I search for "adds", it works pretty well. However, when I perform a search that spans nodes, it doesn't highlight the content very effectively.

Context
I think it's necessary to tackle this issue. Initially, I planned to start with Range.intersection, by calculating the overlapping ranges at the parent node and judging the intersection of multiple nodes to address this issue. However, I realized that this might impose a burden on the rendering performance of Slate, as it may need to constantly traverse nodes for searching.

Therefore, I resolved this issue here by modifying the example of the site. By clearly identifying the content to be searched and the boundaries of the split nodes to obtain smaller values to form a range, even if the content being searched is very long, it will only save the search content within its own range.

Additionally, I noticed that there's no option for site changes in the changeset config. Therefore, I believe that this change doesn't require a changeset.

Checks

• The new code matches the existing patterns and styles.
• The tests pass with yarn test.
• The linter passes with yarn lint. (Fix errors with yarn fix.)
• The relevant examples still work. (Run examples with yarn start.)
• You've added a changeset if changing functionality. (Add one with yarn changeset add.)

[changeset-bot]

⚠️ No Changeset found

Latest commit: c350dee

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[dylans]

Thanks @WindRunnerMax.

I agree with your sentiment as well (updating the example, for now).