Allow HX-Location to control indicator cleanup

[Ai-Eastern]

Description

Preserve the existing HX-Location behavior by default, while allowing partial-page redirects to opt out with keepIndicators:false in the HX-Location JSON or HCON options.

When disabled, the original request cleans up its indicators and re-enables disabled elements after issuing the follow-up request. The option is consumed by the response-header handler and is not forwarded to the follow-up htmx.ajax() call.

Adds regression coverage for the default and opt-out behavior, guards HX-Refresh/HX-Redirect, and documents the new option.

Fixes #4090

Testing

• RED: npm test -- test/tests/unit/__handleHxHeadersAndMaybeReturnEarly.js — 15 passed, 1 expected failure before the implementation.
• PASS: npm test -- test/tests/unit/__handleHxHeadersAndMaybeReturnEarly.js — 16 passed, 0 failed.
• PASS: npm test -- test/tests/unit/__handleHxHeadersAndMaybeReturnEarly.js test/tests/attributes/hx-indicator.js — 21 passed, 0 failed.
• PASS: npm test — 1784 passed, 0 failed, 4 skipped.
• PASS: git diff --check.
• PASS: npm run check:content — all source, extension API documentation, and web-types checks passed (using the bundled Python runtime with UTF-8 mode).

No generated dist files are included.

[Ai-Eastern]

@MichaelWest22 I've updated this PR based on your suggestion: the existing behavior is preserved by default, while HX-Location can now set keepIndicators:false for partial-page replacements. I also added regression tests and documentation. Would you mind taking a look when you have a chance?

[MichaelWest22]

@Ai-Eastern thanks. i've had another look and I think we can maybe do a better solution to just get hx-location to pass the indicators and disabled elements down to the next ajax request in a chain so it can tidy them up naturally. This avoid having to know to set keepIndicators manually when required as i had originally suggested. Opened #4097 with this version

[Ai-Eastern]

Thanks for taking another look. Passing the existing indicator and disabled-element state through the HX-Location request chain is cleaner and avoids requiring callers to opt into cleanup manually. Closing this in favor of #4097.