flutter_package / fluttertpc_get

- adds automatic `onClose()` management to instances created with `Get.create()` (only applies to Routes).
- adds docs for the feature description and limitation.

Replying to an issue spotted by @Quent on Discord, this fixes the lifecycle
( `onInit()`, `onReady()`).
`onClose()` has to be called manually by the dev in the created instance.

chore: Fix example app (missing activity)

update to Getx 3.10.1

Fixes issue described in #569 and #585. `tag` was not being registered for `lazyPut()`;

new README docs section

Minor Code Reduction without affecting functionality

chore: add analyzer to PR check pipeline

Get.delete update and some missing docs

- Added `Get.delete( force)` which was missing to manually remove permanent instances with Get.put().
- added missing doc comment to isPrepared()

subtle Rx improvements and docs.

Co-authored-by: Nipodemos <nipodemos13@gmail.com>

add `@override` to the suggestion, `toJson()` and `fromJson()`

Co-authored-by: Nipodemos <nipodemos13@gmail.com>

Co-authored-by: Nipodemos <nipodemos13@gmail.com>

- fixes #470
- added main README section docs called "Useful tips" where i mentioned some stuffs..

Co-authored-by: Nipodemos <nipodemos13@gmail.com>

- small comment fix (https://github.com/jonataslaw/getx/pull/560#commitcomment-42045326)
- added `RxBool.toggle()`as an easy shortcut for switching true/false values.
- added `_RxImp.nil()` to easily set the value to `null` (`nil` comes from LISP :P) seems to be a useful sometimes, for instance if using `RxString` in `TextField.decoration.errorText` is the only way to avoid the "error state".
- adds missing docs to Rx classes.

rx list sort method compare param passed

This reverts commit 878bfe51.

This reverts commit aa7fb11d.

dialog style