feat(led_strip): support led strip group based on parlio_tx

[Kainarx]

Closes #427

[Copilot]

Pull Request Overview

This PR introduces support for LED strip groups using the Parallel IO (PARLIO) backend while also adding an asynchronous refresh API and runtime GPIO switching for the RMT backend. Key changes include:

• Adding new group APIs (led_strip_group_get_strip_handle and led_strip_group_del) and the corresponding type definitions.
• Integrating the PARLIO backend by adding led_strip_parlio_config_t and led_strip_new_parlio_group.
• Updating documentation, examples, version numbers, and build configuration files.

Reviewed Changes

Copilot reviewed 25 out of 25 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
led_strip/src/led_strip_api.c	Added new API implementations for led strip group and GPIO switching.
led_strip/interface/led_strip_interface.h	Declared new group interface and added async refresh API documentation.
led_strip/include/led_strip_types.h	Introduced led_strip_group_handle_t and encoder timings structures.
led_strip/include/led_strip_spi.h	Updated SPI configuration to use a named extra config structure.
led_strip/include/led_strip_parlio.h	Added Parallel IO backend specific configurations and API declaration.
led_strip/include/led_strip.h	Declared group APIs and updated documentation for async refresh and GPIO.
led_strip/idf_component.yml	Bumped component version to 3.1.0 and updated metadata.
led_strip/examples/*	Added or updated examples and tests for PARLIO, SPI, and RMT backends.
led_strip/api.md	Updated API documentation to include new group and async refresh APIs.
led_strip/CMakeLists.txt & .build-test-rules.yml	Adjusted build configuration and test rules for PARLIO support.
led_strip/CHANGELOG.md	Documented new features and changes for version 3.1.0.

Comments suppressed due to low confidence (2)

led_strip/interface/led_strip_interface.h:140

• Typo in parameter description: 'Retured' should be corrected to 'Returned'.

 * @param ret_strip: Retured LED strip handle

led_strip/api.md:681

• Typo in the documentation: 'Retured' should be 'Returned'.

- `ret_strip` Retured LED strip handle