Add initial configs for obsidian and copy logic for files

obsidian seems to only have a per-vault config approach, so my approach
is to define settings within .config/obsidian, then copy to vault dirs

src_files/.config/obsidian/appearance.json

@@ -0,0 +1,4 @@
+{
+  "theme": "obsidian",
+  "accentColor": "#2f930e"
+}