Update nvim config: terminal layout, colorschemes, and vimade

Reposition terminal and Claude Code windows relative to current window
at 30% height, add multiple colorschemes with oxocarbon as default,
and add vimade plugin with blocklist to keep Claude terminal unfaded.

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

nvim/lua/plugins/vimade.lua

@@ -0,0 +1,13 @@
+return {
+  "TaDaa/vimade",
+  event = "WinNew",
+  opts = {
+    recipe = { "minimalist", { animate = true } },
+    fadelevel = 0.8,
+    blocklist = {
+      claude_terminal = {
+        buf_opts = { ft = "snacks_terminal" },
+      },
+    },
+  },
+}