feat: add org-indent-mode-turns-on-hiding-stars equivalent

[PriceHiller]

Follow on from #627.

Bullet points:

• Added new config flag: org_indent_mode_turns_on_hiding_stars which is enabled by default
• Added docs reflecting new configuration flag

Crosses another one off my list of indent mode features.

[kristijanhusak]

Let's just rebase this from nightly and make a PR target there. Thanks.

[kristijanhusak]

Lets just move things around a bit so it works only for buffers with org_indent_mode.

[PriceHiller]

As an aside, do you mind if I PR a quick make format to nightly? Getting assaulted by the linter on every pre-push is driving me ever so slightly insane.

[kristijanhusak]

I formatted the code on nightly, you can rebase.

Regarding the PR, it works ok, but the hl group for hiding the stars is not applied.

We also need these changes:

diff --git a/lua/orgmode/colors/highlights.lua b/lua/orgmode/colors/highlights.lua
index dcb1a7a..618095e 100644
--- a/lua/orgmode/colors/highlights.lua
+++ b/lua/orgmode/colors/highlights.lua
@@ -102,13 +102,11 @@ function M.define_org_headline_colors(faces)
   for _, face in pairs(faces) do
     table.insert(contains, face)
   end
-  if config.org_hide_leading_stars then
-    if not ts_highlights_enabled then
-      vim.cmd([[syn match OrgHideLeadingStars /^\*\{2,\}/me=e-1 contained]])
-    end
-    vim.cmd([[hi default OrgHideLeadingStars ctermfg=0 guifg=bg]])
-    table.insert(contains, 'OrgHideLeadingStars')
+  if not ts_highlights_enabled then
+    vim.cmd([[syn match OrgHideLeadingStars /^\*\{2,\}/me=e-1 contained]])
   end
+  vim.cmd([[hi default OrgHideLeadingStars ctermfg=0 guifg=bg]])
+  table.insert(contains, 'OrgHideLeadingStars')
   for i, color in ipairs(headline_colors) do
     local j = i
     while j < 40 do

[PriceHiller]

I applied your patch and rebased on top of nightly for the formatting

[kristijanhusak]

Looks good, thanks!