…blockwise mode

Problem:  setreg() doesn't correctly handle mbyte chars in blockwise
          mode
Solution: use mb_ptr2len_len function pointer (Yee Cheng Chin)

setreg() will automatically calculate the width when a blockwise mode is
specified, but it does not properly calculate the line widths of mbyte
characters when value is passed as newline-terminated string. It does
work when value is passed as a list of lines though.

Fix this by properly using the mbyte function pointer to increment the
loop counter.

closes: vim/vim#16596

vim/vim@a17f8bf

Co-authored-by: Yee Cheng Chin <ychin.git@gmail.com>

…blockwise mode

Problem:  setreg() doesn't correctly handle mbyte chars in blockwise
          mode
Solution: use mb_ptr2len_len function pointer (Yee Cheng Chin)

setreg() will automatically calculate the width when a blockwise mode is
specified, but it does not properly calculate the line widths of mbyte
characters when value is passed as newline-terminated string. It does
work when value is passed as a list of lines though.

Fix this by properly using the mbyte function pointer to increment the
loop counter.

closes: vim/vim#16596

vim/vim@a17f8bf

Co-authored-by: Yee Cheng Chin <ychin.git@gmail.com>

Apple "Intelligence" Writing Tools was previously not working correctly
with MacVim. When the user chooses to replace the original selection
with the updated texts, MacVim mistreats the input and treat them as
commands instead of raw texts. The reason was that even though this
service uses the NSServicesMenuRequestor API to obtain the selected
texts, it does not use it to send over the replacement. Instead, it uses
NSTextInput's `insertText:replacementRange` to do so instead, which we
never implemented properly. The reason behind this choice was probably
because Writing Tools first shows a UI with user interaction and has a
delay between obtaining the texts and replacing them, like a regular
Services menu. This means the selection may already be invalid by the
time it requests a replacement.

To fix this, add a new IPC API `replaceSelectedText` to replace the
selected texts and redirect `insertText:replacementRange` to use it if
the replacement range is non-empty. This isn't the most correct
implementation of the protocol but should work in most cases. We don't
have a way to implement it "correctly" as MacVim does not have easy
access to Vim's internal text storage. Also make sure the Service
menu uses this API (for things like "convert to full width" and
Traditional/Simplified Chinese conversions). The old method of simple
injecting a normal mode command `s` before the text was horribly buggy.
It also works with visual block selection properly now.

The implementation uses Vim's register put functionality because Vim
doesn't have an API to simply replace a block of text, and everything
has to go through registers. At the same time, replace the
implementation for the old `selectedText` IPC API to not do this,
because Vim *did* end an API to do so for obtaining texts (via
`getregion()`) and it's more stable to use this than to manually
cache/restore registers.

Related: vim/vim#16596 (fixes `setreg()` which this uses)

Fix macvim-dev#1512

Apple "Intelligence" Writing Tools was previously not working correctly
with MacVim. When the user chooses to replace the original selection
with the updated texts, MacVim mistreats the input and treat them as
commands instead of raw texts. The reason was that even though this
service uses the NSServicesMenuRequestor API to obtain the selected
texts, it does not use it to send over the replacement. Instead, it uses
NSTextInput's `insertText:replacementRange` to do so instead, which we
never implemented properly. The reason behind this choice was probably
because Writing Tools first shows a UI with user interaction and has a
delay between obtaining the texts and replacing them, like a regular
Services menu. This means the selection may already be invalid by the
time it requests a replacement.

To fix this, add a new IPC API `replaceSelectedText` to replace the
selected texts and redirect `insertText:replacementRange` to use it if
the replacement range is non-empty. This isn't the most correct
implementation of the protocol but should work in most cases. We don't
have a way to implement it "correctly" as MacVim does not have easy
access to Vim's internal text storage. Also make sure the Service
menu uses this API (for things like "convert to full width" and
Traditional/Simplified Chinese conversions). The old method of simple
injecting a normal mode command `s` before the text was horribly buggy.
It also works with visual block selection properly now.

The implementation uses Vim's register put functionality because Vim
doesn't have an API to simply replace a block of text, and everything
has to go through registers. At the same time, replace the
implementation for the old `selectedText` IPC API to not do this,
because Vim *did* end an API to do so for obtaining texts (via
`getregion()`) and it's more stable to use this than to manually
cache/restore registers.

Related: vim/vim#16596 (fixes `setreg()` which this uses)

Fix macvim-dev#1512