feat(lua): show proper verbose output for lua configuration

`:verbose` didn't work properly with lua configs (For example:
    options or keymaps are set from lua, just say that they were set
    from lua, doesn't say where they were set at.

This fixes that issue. Now `:verbose` will provide filename and line no
when option/keymap is set from lua.

Changes:
  - compiles lua/vim/keymap.lua as vim/keymap.lua
 - When souring a lua file current_sctx.sc_sid is set to SID_LUA
 - Moved finding scripts SID out of `do_source()` to `get_current_script_id()`.
   So it can be reused for lua files.
 - Added new function `nlua_get_sctx` that extracts current lua scripts
   name and line no with debug library. And creates a sctx for it.
     NOTE: This function ignores C functions and blacklist which
     currently contains only vim/_meta.lua so vim.o/opt wrappers aren't
     targeted.
 - Added function `nlua_set_sctx` that changes provided sctx to current
   lua scripts sctx if a lua file is being executed.
 - Added tests in tests/functional/lua/verbose_spec.lua
 - add primary support for additional types (:autocmd, :function, :syntax) to lua verbose
    Note: These can't yet be directly set from lua but once that's possible
    :verbose should work for them hopefully :D
 - add :verbose support for nvim_exec & nvim_command within lua
    Currently auto commands/commands/functions ... can only be defined
    by nvim_exec/nvim_command this adds support for them. Means if those
    Are defined within lua with vim.cmd/nvim_exec :verbose will show their
    location . Though note it'll show the line no on which nvim_exec call was made.

1 files changed, 6 insertions, 1 deletions

diff --git a/src/nvim/api/vimscript.c b/src/nvim/api/vimscript.c
index 640144b234..4123674fe7 100644
--- a/src/nvim/api/vimscript.c
+++ b/src/nvim/api/vimscript.c
@@ -37,7 +37,7 @@
 /// @param[out] err Error details (Vim error), if any
 /// @return Output (non-error, non-shell |:!|) if `output` is true,
 ///         else empty string.
-String nvim_exec(String src, Boolean output, Error *err)
+String nvim_exec(uint64_t channel_id, String src, Boolean output, Error *err)
   FUNC_API_SINCE(7)
 {
   const int save_msg_silent = msg_silent;
@@ -52,11 +52,16 @@ String nvim_exec(String src, Boolean output, Error *err)
   if (output) {
     msg_silent++;
   }
+
+  const sctx_T save_current_sctx = api_set_sctx(channel_id);
+
   do_source_str(src.data, "nvim_exec()");
   if (output) {
     capture_ga = save_capture_ga;
     msg_silent = save_msg_silent;
   }
+
+  current_sctx = save_current_sctx;
   try_end(err);
 
   if (ERROR_SET(err)) {