Restructure modules/shared and update all imports

- Rename modules/hosts/common to modules/shared
- Split shared into home/general, home/linux, and nixos subdirectories
- Update all import paths in lib/ and modules/hosts/
- Fix hardcoded /Users/ path to use config.home.homeDirectory
- Update .sops.yaml path for secrets

modules/hosts/common/files/nvim/lua/disabled/nvim-tree.lua

@@ -1,11 +0,0 @@
-return{
-  "nvim-tree/nvim-tree.lua",
-  config = function ()
-    vim.g.loaded_netrw = 1
-    vim.g.loaded_netrwPlugin = 1
-
-    require('nvim-tree').setup()
-
-    vim.keymap.set('n', '<c-n>', ':NvimTreeFindFileToggle<CR>')
-  end
-}