docs(linter): Add configuration docs to no-useless-escape lint rule.

[connorshea]

Also add missing text for "Why is this bad?" section. I've updated this to use the autogen docs rather than an explicit Options section, since that seems to be the preferred implementation path for this kind of addition.

Part of #14743.

Results in:

## Configuration

This rule accepts a configuration object with the following properties:

### allowRegexCharacters

type: `string[]`

default: `[]`

An array of characters that are allowed to be escaped unnecessarily in regexes.

[graphite-app]

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[Copilot]

Pull Request Overview

This PR adds comprehensive documentation to the no-useless-escape lint rule, including missing content for the "Why is this bad?" section and a new "Options" section with details about the allowRegexCharacters configuration option.

• Added explanatory text for why unnecessary escapes are problematic
• Added complete Options documentation with configuration details and JSON example

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[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

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[camc314]

Thank yoU!

[codspeed-hq]

CodSpeed Performance Report

Merging #14791 will not alter performance

_{Comparing connorshea:cshea/no-useless-escape (9b2e7fb) with main (7be9489)¹}

Summary

✅ 4 untouched
⏩ 33 skipped²

Footnotes

1. No successful run was found on main (6d5f7b2) during the generation of this report, so 7be9489 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 33 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩