feat(nvim): v0.11: Use native LSP, Completion, Diagnostics

- Move all language LSP configurations to `nvim/lsp`
- Move nvim LSP configurations to `nvim/lua/core`
- Remove LSP attach keymaps where default ones exists and are usable
- Reorged LSP attach keymaps per plugin
- Move Lazy.nvim configurations to `nvim/lua/core`
- `nvim/init.lua` cleaned to only load other files
- Uniform diagnostics symbols across lualine & gutter

common/.config/nvim/lsp/rust_analyzer.lua

@@ -0,0 +1 @@
+return {}