Enhance ElementFilter

[python-and-fiction]

For ElementFilter's __init__\within\not_within\exclude method:
marker parameter supports string list and string with whitespace in string list now.
We can do it in ElementFilter like element's mark method.

from nicegui import ui,ElementFilter

with ui.card():
    ui.button('button A')
    ui.label('label A_A').mark('A')
    ui.label('label A_B').mark('A','B','AB')

with ui.card():
    ui.button('button B')
    ui.label('label B_B').mark('B')
    ui.label('label B_A').mark('B A BA')

ElementFilter(marker=['A','B BA']).classes('bg-red')
ElementFilter(marker=['B']).exclude(marker=['A AB']).classes('text-2xl')

ui.run()

[python-and-fiction]

Now ElementFilter's method supports constructing in one step.

from nicegui import ui,ElementFilter

with ui.row():
    with ui.card():
        ui.button('button A')
        ui.label('label A_A')
        ui.label('label A_B')

with ui.card():
    ui.button('button B')
    ui.label('label B_B')
    ui.label('label B_A')

with ui.column():
    with ui.list():
        ui.button('button A')
        ui.label('label A_A')
        ui.label('label A_B')

ElementFilter(kind=[ui.button,ui.label]).within(kind=[ui.card,ui.row]).classes('bg-red')
ElementFilter(kind=[ui.button,ui.label]).not_within(kind=[ui.card,ui.row]).classes('text-2xl')
ElementFilter(kind=[ui.button,ui.label]).exclude(kind=[ui.label]).classes('text-green')

ui.run()

[python-and-fiction]

I make a tab for beginner to learn ElementFilter's method, but I don't know how to insert it in document correctly, can anyone help me? Thank you so much!

Match type for parameters in ElementFilter's method:
| ElementFilter's method | `__init__` | `within` | `not_within` | `exclude` |
| ---------------------- | ---------- | -------- | ------------ | --------- |
| parameter `kind`       | any/or     | all/and  | any/or       | any/or    |
| parameter `content`    | all/and    | ----     | ----         | any/or    |
| parameter `instance`   | ----       | all/and  | any/or       | ----      |
| parameter `marker`     | all/and    | all/and  | any/or       | any/or    |

[rodja]

Thanks @python-and-fiction. The review and commenting would be much easier if this would be two separate pull requests.

About the whitespace in list elements:
What would be use cases for this? Why would somebody want to write ElementFilter(marker=['A','B BA']) instead of ElementFilter(marker=['A','B', 'BA']) or ElementFilter(marker=['A B BA'])?

About the list of kinds (and the table):
We wanted the __init__ and within methods to be "all/and" to not need that table. If someone needs multiple kinds they could write itertools.chain(ElementFilter(kind=ui.button), ElementFilter(kind=ui.label)).

[python-and-fiction]

@rodja Hi,I am writing a chinese guide of nicegui for beginner. When I learn element's mark methond, I found that mark method supports mark('A','B BA') .
In mark('A','B BA') , _markers will be ['A','B','BA']. So I think ElementFilter's method should be like this.
As for table, I also make a chinese table for beginner, it is easier for me to learn and review. Maybe beginner who use English need it. I don't know.