feat(nvim_open_term): convert LF => CRLF (#26384)

Problem:
Unlike termopen(), nvim_open_term() PTYs do not carriage-return the
cursor on newline ("\n") input.

    nvim --clean
    :let chan_id = nvim_open_term(1, {})
    :call chansend(chan_id, ["here", "are", "some", "lines"])

Actual behavior:

    here
        are
           some
               lines

Expected behaviour:

    here
    are
    some
    lines

Solution:
Add `force_crlf` option, and enable it by default.

2 files changed, 3 insertions, 1 deletions

diff --git a/src/nvim/api/keysets_defs.h b/src/nvim/api/keysets_defs.h
index d1cbe43de0..c0daa0ca74 100644
--- a/src/nvim/api/keysets_defs.h
+++ b/src/nvim/api/keysets_defs.h
@@ -344,4 +344,5 @@ typedef struct {
 typedef struct {
   OptionalKeys is_set__open_term_;
   LuaRef on_input;
+  Boolean force_crlf;
 } Dict(open_term);
diff --git a/src/nvim/api/vim.c b/src/nvim/api/vim.c
index a52d7493e3..2f3d527b9e 100644
--- a/src/nvim/api/vim.c
+++ b/src/nvim/api/vim.c
@@ -985,6 +985,7 @@ fail:
 ///            as a "\r", not as a "\n". |textlock| applies. It is possible
 ///            to call |nvim_chan_send()| directly in the callback however.
 ///                 ["input", term, bufnr, data]
+///          - force_crlf: (boolean, default true) Convert "\n" to "\r\n".
 /// @param[out] err Error details, if any
 /// @return Channel id, or 0 on error
 Integer nvim_open_term(Buffer buffer, Dict(open_term) *opts, Error *err)
@@ -1002,7 +1003,6 @@ Integer nvim_open_term(Buffer buffer, Dict(open_term) *opts, Error *err)
   }
 
   LuaRef cb = LUA_NOREF;
-
   if (HAS_KEY(opts, open_term, on_input)) {
     cb = opts->on_input;
     opts->on_input = LUA_NOREF;
@@ -1020,6 +1020,7 @@ Integer nvim_open_term(Buffer buffer, Dict(open_term) *opts, Error *err)
     .write_cb = term_write,
     .resize_cb = term_resize,
     .close_cb = term_close,
+    .force_crlf = GET_BOOL_OR_TRUE(opts, open_term, force_crlf),
   };
   channel_incref(chan);
   terminal_open(&chan->term, buf, topts);