Update strings.json

[sarthakjalan05]

What GitHub issue does this PR apply to?

Resolves #717

What changed and why?

Added more detailed options under the String Formatting section to include signed/unsigned integer formatting and floating-point formatting.
Renamed the basic format operations to be more specific to how C works.

(If editing website code) Please add screenshots

Checklist

• I claimed any associated issue(s) and they are not someone else's
• I have looked at documentation to ensure I made any revisions correctly
• I tested my changes locally to ensure they work
• For language files, I have validated the edited files are valid JSON and data shows up correctly
• For website code edits, I have added or edited any appropriate unit tests for my changes

Any additional comments or things to be aware of while reviewing?

[geekygirlsarah]

I think this looks good, and good catch on the typos. Thanks!

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