chore: clean up dotfiles and add gitignore whitelist

Switch to whitelist-based .gitignore to only track essential configs:
nvim, yazi, kitty, zsh, ideavim, karabiner, tmux, scripts, starship.
Remove history, compiled files, and plugin dirs from tracking.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

nvim/lua/snippets/markdown.lua

@@ -6,18 +6,42 @@ local f = ls.function_node
 
 -- Get current date in YYYY-MM-DD format
 local function date()
-  return os.date("%Y-%m-%d")
+	return os.date("%Y-%m-%d")
 end
 
 return {
-  s("env", {
-    t({"---",
-       "title: "}), i(1, "Title"), t({"",
-       "tags: ["}), i(2, "tag1, tag2"), t({"]",
-       "date: "}), f(date, {}), t({"",
-       "---", ""}),
-    i(0),
-  }),
-}  
+	s("env", {
+		t({
+			"---",
+			"title: ",
+		}),
+		i(1, "Title"),
+		t({ "", "tags: [" }),
+		i(2, "tag1, tag2"),
+		t({ "]", "date: " }),
+		f(date, {}),
+		t({ "", "---", "" }),
+		i(0),
+	}),
 
+	s(
+		"ippd",
+		t({
+			"Institute of Polymer Processing and Digital Transformation",
+		})
+	),
 
+	s(
+		"TN",
+		t({
+			"Thomas Naderer",
+		})
+	),
+
+	s(
+		"GBW",
+		t({
+			"Gerald Berger-Weber",
+		})
+	),
+}