let AIChat respect window placement mods like :vert, :tab, ...

[Konfekt]

It is only possible to open the buffer with the open cmd, but while often a new tab is convenient, sometimes a horiziontal or vertical tab is more suitable to keep track of the edited buffer.

How about letting :AI(New)Chat using <mods> to respect a supplied :vert/tab/ .... ?

#  doc/map.txt (lines 1827-1847)
	<mods>  The command modifiers, if specified. Otherwise, expands to
		nothing. Supported modifiers are |:aboveleft|, |:belowright|,
		|:botright|, |:browse|, |:confirm|, |:hide|, |:horizontal|,
		|:keepalt|, |:keepjumps|, |:keepmarks|, |:keeppatterns|,
		|:leftabove|, |:lockmarks|, |:noautocmd|, |:noswapfile|
		|:rightbelow|, |:sandbox|, |:silent|, |:tab|, |:topleft|,
		|:unsilent|, |:verbose|, and |:vertical|.
		Note that |:filter| is not supported.
		Examples: >
		    command! -nargs=+ -complete=file MyEdit
				\ for f in expand(<q-args>, 0, 1) |
				\ exe '<mods> split ' .. f |
				\ endfor

		    function! SpecialEdit(files, mods)
			for f in expand(a:files, 0, 1)
			    exe a:mods .. ' split ' .. f
			endfor
		    endfunction
		    command! -nargs=+ -complete=file Sedit
				\ call SpecialEdit(<q-args>, <q-mods>)