feat(health): improvements to :checkhealth #40935

Changes:
- Removed the blank line before the first healthcheck header.
- Fixed a bug where the entire "Terminal" section of `vim.health` would
  not appear if the `infocmp` executable was not found.
- Fixed a typo in `vim.lsp` when displaying the LSP log level.

runtime/lua/vim/health.lua

@@ -459,7 +459,6 @@ function M._check(eap)
   for _, name in ipairs(names) do
     local value = healthchecks[name]
     progress_msg('running', check_idx, 'checking %s', name)
-    check_idx = check_idx + 1
     local func = value[1]
     local type = value[2]
     s_output = {}
@@ -508,7 +507,9 @@ function M._check(eap)
     end
     s_output[#s_output + 1] = ''
     s_output = vim.list_extend(header, s_output)
-    vim.fn.append(vim.fn.line('$'), s_output)
+    vim.api.nvim_buf_set_lines(0, check_idx == 1 and 0 or -1, -1, true, s_output)
+
+    check_idx = check_idx + 1
   end
 
   progress_msg('success', nil, 'checks done')

runtime/lua/vim/health/health.lua

@@ -486,15 +486,12 @@ local function check_graphics()
   end
 end
 
-local function check_terminal()
+-- Note: this is part of check_terminal().
+local function check_infocmp()
   if vim.fn.executable('infocmp') == 0 then
     return
   end
 
-  health.start('Terminal')
-
-  check_graphics()
-
   local cmd = { 'infocmp', '-L' }
   local ok, out = system(cmd)
   local kbs_entry = vim.fn.matchstr(out, 'key_backspace=[^,[:space:]]*')
@@ -527,6 +524,14 @@ local function check_terminal()
       )
     )
   end
+end
+
+local function check_terminal()
+  health.start('Terminal')
+
+  check_graphics()
+
+  check_infocmp()
 
   for _, env_var in ipairs({
     'XTERM_VERSION',

runtime/lua/vim/lsp/health.lua

@@ -24,7 +24,7 @@ local function check_log()
   local log = vim.lsp.log
   local current_log_level = log.get_level()
   local log_level_string = log.levels[current_log_level] ---@type string
-  report_info(string.format('LSP log level : %s', log_level_string))
+  report_info(string.format('LSP log level: %s', log_level_string))
 
   if current_log_level < log.levels.WARN then
     report_warn(