feat: add more default icons opts.link.custom (#565)

* feat: add more default icons `opts.link.custom`

Added some icons for well-known companies that do have their logo available as nerdfont glyph.

* fix: added linkedin default icon

Author: chrisgrieser

lua/render-markdown/settings.lua

@@ -1287,13 +1287,20 @@ M.link.default = {
     -- | highlight | optional highlight for 'icon', uses fallback highlight if empty |
     custom = {
         web = { pattern = '^http', icon = '󰖟 ' },
+        apple = { pattern = "apple%.com", icon = " " },
         discord = { pattern = 'discord%.com', icon = '󰙯 ' },
         github = { pattern = 'github%.com', icon = '󰊤 ' },
         gitlab = { pattern = 'gitlab%.com', icon = '󰮠 ' },
         google = { pattern = 'google%.com', icon = '󰊭 ' },
+        hackernews = { pattern = "ycombinator%.com", icon = " " },
+        linkedin = { pattern = "linkedin%.com", icon = "󰌻 " },
+        microsoft = { pattern = "microsoft%.com", icon = " " },
         neovim = { pattern = 'neovim%.io', icon = ' ' },
         reddit = { pattern = 'reddit%.com', icon = '󰑍 ' },
+        slack = { pattern = "slack%.com", icon = "󰒱 " },
         stackoverflow = { pattern = 'stackoverflow%.com', icon = '󰓌 ' },
+        steam = { pattern = "steampowered%.com", icon = " " },
+        twitter = { pattern = "x%.com", icon = " " },
         wikipedia = { pattern = 'wikipedia%.org', icon = '󰖬 ' },
         youtube = { pattern = 'youtube%.com', icon = '󰗃 ' },
     },