Problem:  Cannot control cursor positioning of getchar().
Solution: Add "cursor" flag to {opts}, with possible values "hide",
          "keep" and "msg".

related: vim/vim#10603
closes: vim/vim#16569

https://github.com/vim/vim/commit/edf0f7db28f87611368e158210e58ed30f673098

Problem:  getchar() can't distinguish between C-I and Tab.
Solution: Add {opts} to pass extra flags to getchar() and getcharstr(),
          with "number" and "simplify" keys.

related: vim/vim#10603
closes: vim/vim#16554

https://github.com/vim/vim/commit/e0a2ab397fd13a71efec85b017d5d4d62baf7f63

Cherry-pick tv_dict_has_key() from patch 8.2.4683.

Problem:  no way to get current selected item in a async context
Solution: add completed flag to show the entries of currently selected
          index item (glepnir)

closes: vim/vim#16451

https://github.com/vim/vim/commit/037b028a2219d09bc97be04b300b2c0490c4268d

Co-authored-by: glepnir <glephunter@gmail.com>

Co-authored-by: Axel <axelhjq@gmail.com>
Co-authored-by: Colin Kennedy <colinvfx@gmail.com>
Co-authored-by: Daiki Noda <sys9kdr@users.noreply.github.com>
Co-authored-by: Evgeni Chasnovski <evgeni.chasnovski@gmail.com>
Co-authored-by: Jean-Jacq du Plessis <1030058+jj-du-plessis@users.noreply.github.com>
Co-authored-by: Juan Giordana <juangiordana@gmail.com>
Co-authored-by: Lincoln Wallace <locnnil0@gmail.com>
Co-authored-by: Matti Hellström <hellstrom@scm.com>
Co-authored-by: Steven Locorotondo <steven.locorotondo@justeattakeaway.com>
Co-authored-by: Yochem van Rosmalen <git@yochem.nl>
Co-authored-by: glepnir <glephunter@gmail.com>
Co-authored-by: ifish <fishioon@live.com>

Problem:  v:stacktrace has wrong type in Vim9 script.
Solution: Change the type to t_list_dict_any.  Fix grammar in docs.
          (zeertzjq)

closes: vim/vim#16390

https://github.com/vim/vim/commit/6655bef33047b826e0ccb8c686f3f57e47161b1c

Problem:  exception handling can be improved
Solution: add v:stacktrace and getstacktrace()

closes: vim/vim#16360

https://github.com/vim/vim/commit/663d18d6102f40d14e36096ec590445e61026ed6

Co-authored-by: ichizok <gclient.gaap@gmail.com>
Co-authored-by: Naruhiko Nishino <naru123456789@gmail.com>

vim-patch:9.1.0983: not able to get the displayed items in complete_info()

Problem:  not able to get the displayed items in complete_info()
          (Evgeni Chasnovski)
Solution: return the visible items via the "matches" key for
          complete_info() (glepnir)

fixes: vim/vim#10007
closes: vim/vim#16307

https://github.com/vim/vim/commit/d4088edae21659e14ab5f763c820f4eab9d36981

Problem:
`termopen` has long been a superficial wrapper around `jobstart`, and
has no real purpose. Also, `vim.system` and `nvim_open_term` presumably
will replace all features of `jobstart` and `termopen`, so centralizing
the logic will help with that.

Solution:
- Introduce `eval/deprecated.c`, where all deprecated eval funcs will live.
- Introduce "term" flag of `jobstart`.
- Deprecate `termopen`.