feat(nvim): reorganize and modernize Neovim configuration

- Remove deprecated config files: git-ref.lua, git-signs.lua, diffview-config.lua, lsp-lines-config.lua, neotree-config.lua, fidget-spinner.lua, silicon-config.lua, telescope-config.lua, llm.lua
- Add new configuration files: diagnostics-config.lua, git-config.lua, llm-config.lua, snacks-config.lua
- Update existing config files: base.lua, dap-config.lua, init.lua, lsp-config.lua, lualine-config.lua, noice-config.lua, octo-config.lua, toggleterm-config.lua, which-key-config.lua
- Update nvim and opencode module configurations

modules/home/programs/terminal/nvim/config/lua/diagnostics-config.lua

@@ -0,0 +1,35 @@
+-- Diagnostics Mappings
+local diagnostics_active = true
+local toggle_diagnostics = function()
+	diagnostics_active = not diagnostics_active
+	if diagnostics_active then
+		vim.diagnostic.enable()
+	else
+		vim.diagnostic.disable()
+	end
+end
+
+local diagnostics_loclist_active = false
+local toggle_diagnostics_loclist = function()
+	diagnostics_loclist_active = not diagnostics_loclist_active
+	if diagnostics_loclist_active then
+		vim.diagnostic.setloclist()
+	else
+		vim.cmd("lclose")
+	end
+end
+
+-- Create KeyMaps
+local opts = { noremap = true, silent = true }
+vim.keymap.set("n", "<leader>qN", function()
+	vim.diagnostic.goto_prev({ float = false })
+end, vim.tbl_extend("force", { desc = "Previous Diagnostic" }, opts))
+vim.keymap.set("n", "<leader>qe", vim.diagnostic.open_float,
+	vim.tbl_extend("force", { desc = "Open Diagnostics" }, opts))
+vim.keymap.set("n", "<leader>qt", toggle_diagnostics,
+	vim.tbl_extend("force", { desc = "Toggle Inline Diagnostics" }, opts))
+vim.keymap.set("n", "<leader>qn", function()
+	vim.diagnostic.goto_next({ float = false })
+end, vim.tbl_extend("force", { desc = "Next Diagnostic" }, opts))
+vim.keymap.set("n", "<leader>qq", toggle_diagnostics_loclist,
+	vim.tbl_extend("force", { desc = "Toggle Diagnostic List" }, opts))