nvim: Restructure lua dir

Moved plugins into individual component module files which are
automatically required by lazy.nvim. Should make everything a tiny bit
more modular, or at least prepare the way for true modularity if I ever
have the time on my hands to ensure everything works with missing
modules.

Moved core settings into their own directory (`core`), and created a
`personal` folder which contains functions/plugins I wrote that do not
necessarily have to be their own imported plugin yet.

Finally, extended the utility functions a little, so we can detect if a
plugin exists and change e.g. key maps based on that (once again,
extending modularity a little more). Some simple attempts have been made
at that in the `mappings.lua` file, though it is nowhere near extensive
yet - most keymaps are still set regardless of plugin availability.

However, with this slimmer base to work off of, I feel more confident in
changing future things about this setup a little more ad-hoc without
having as many ripple repercussions as before.

nvim/.config/nvim/lua/plugins/config/lsp.lua

@@ -0,0 +1,168 @@
+vim.diagnostic.config({ virtual_text = true })
+vim.fn.sign_define("DiagnosticSignError", { text = "✘", texthl = "DiagnosticSignError" })
+vim.fn.sign_define("DiagnosticSignWarn", { text = "", texthl = "DiagnosticSignWarn" })
+vim.fn.sign_define("DiagnosticSignInfo", { text = "", texthl = "DiagnosticSignInfo" })
+vim.fn.sign_define("DiagnosticSignHint", { text = "", texthl = "DiagnosticSignHint" })
+
+local lsp = require("lsp-setup")
+
+local servers = {
+	ansiblels = {},
+	arduino_language_server = {},
+	astro = {},
+	bashls = {},
+	beancount = {},
+	clangd = {},
+	cssls = {},
+	docker_compose_language_service = {},
+	dockerls = {},
+	emmet_ls = {},
+	gopls = {},
+	julials = {},
+	lua_ls = {
+		settings = {
+			Lua = {
+				diagnostics = { globals = { "vim" } },
+				-- enable when working on neovim stuff. Takes *long* to load
+				-- workspace = { library = vim.api.nvim_get_runtime_file("", true) },
+				telemetry = { enable = false },
+			},
+		},
+	},
+	marksman = {},
+	pyright = {},
+	ruff_lsp = {},
+	tailwindcss = {},
+	taplo = {},
+	texlab = {},
+	tsserver = {},
+	yamlls = {},
+	zk = {},
+}
+
+local function on_attach(client, bufnr)
+	local map = vim.keymap.set
+	map("n", "[d", "<cmd>lua vim.diagnostic.goto_prev()<cr>", { buffer = bufnr, desc = "Previous diagnostic" })
+	map("n", "]d", "<cmd>lua vim.diagnostic.goto_next()<cr>", { buffer = bufnr, desc = "Next diagnostic" })
+	map(
+		"n",
+		"[e",
+		"<cmd>lua vim.diagnostic.goto_prev({severity = vim.diagnostic.severity.ERROR})<cr>",
+		{ buffer = bufnr, desc = "Previous error" }
+	)
+	map(
+		"n",
+		"]e",
+		"<cmd>lua vim.diagnostic.goto_next({severity = vim.diagnostic.severity.ERROR})<cr>",
+		{ buffer = bufnr, desc = "Next error" }
+	)
+
+	local prefix = require("which-key").register
+	prefix({ ["<localleader>l"] = { name = "+lsp" } })
+	map("n", "<localleader>li", "<cmd>LspInfo<cr>", { buffer = bufnr, desc = "Lsp Info" })
+	map(
+		"n",
+		"<localleader>ld",
+		"<cmd>lua vim.diagnostic.open_float()<cr>",
+		{ buffer = bufnr, desc = "Line diagnostics" }
+	)
+	map("n", "<localleader>la", "<cmd>lua vim.lsp.buf.code_action()<cr>", { buffer = bufnr, desc = "Codeactions" })
+	map("n", "<localleader>ln", "<cmd>lua vim.lsp.buf.rename()<cr>", { buffer = bufnr, desc = "Rename element" })
+	if vim.fn.exists(":Telescope") then
+		map("n", "<localleader>lr", "<cmd>Telescope lsp_references<cr>", { buffer = bufnr, desc = "References" })
+		map("n", "<localleader>lf", "<cmd>Telescope lsp_definitions<cr>", { buffer = bufnr, desc = "Definition" })
+		map(
+			"n",
+			"<localleader>lt",
+			"<cmd>Telescope lsp_type_definitions<cr>",
+			{ buffer = bufnr, desc = "Type definition" }
+		)
+		map(
+			"n",
+			"<localleader>lm",
+			"<cmd>Telescope lsp_implementations<cr>",
+			{ buffer = bufnr, desc = "Implementation" }
+		)
+	else
+		map("n", "<localleader>lr", "<cmd>lua vim.lsp.buf.references()<cr>", { buffer = bufnr, desc = "References" })
+		map("n", "<localleader>lf", "<cmd>lua vim.lsp.buf.definition()<cr>", { buffer = bufnr, desc = "Definition" })
+		map(
+			"n",
+			"<localleader>lt",
+			"<cmd>lua vim.lsp.buf.type_definition()<cr>",
+			{ buffer = bufnr, desc = "Type definition" }
+		)
+		map(
+			"n",
+			"<localleader>lm",
+			"<cmd>lua vim.lsp.buf.implementation()<cr>",
+			{ buffer = bufnr, desc = "Implementation" }
+		)
+	end
+	map("n", "<localleader>ll", "<cmd>lua vim.lsp.buf.format()<CR>", { buffer = bufnr, desc = "Format document" })
+	map("n", "K", "<cmd>lua vim.lsp.buf.hover()<cr>", { buffer = bufnr, desc = "Hover definition" })
+	map("n", "<localleader>lc", "<cmd>lua vim.lsp.buf.declaration()<cr>", { buffer = bufnr, desc = "Declaration" })
+	map(
+		"n",
+		"<localleader>ls",
+		"<cmd>lua vim.lsp.buf.signature_help()<cr>",
+		{ buffer = bufnr, desc = "Signature help" }
+	)
+
+	if vim.g.format_on_save then
+		require("lsp-setup.utils").format_on_save(client)
+    end
+end
+
+lsp.setup({
+	default_mappings = false,
+	servers = servers,
+	on_attach = on_attach,
+	inlay_hints = {
+		enabled = vim.fn.has("nvim-0.10") == true and true or false,
+	},
+})
+
+local lspconfig = require("lspconfig")
+
+-- ensure python virtualenv is determined automatically on lsp start
+lspconfig.pyright.setup({
+	on_attach = function(client, _)
+		local python_path, msg = require("util.pyenv").get_path(client.config.root_dir)
+		vim.notify(string.format("%s\n%s", msg, python_path))
+		client.config.settings.python.pythonPath = python_path
+	end,
+})
+-- set up arduino with the help of arduino.nvim plugin
+if require("util").is_available("arduino") then
+	lspconfig.arduino_language_server.setup({
+		on_new_config = require("arduino").on_new_config,
+	})
+end
+
+local null_ls = require("null-ls")
+null_ls.setup({})
+require("mason-null-ls").setup({
+	ensure_installed = { "black", "prettier", "shfmt", "eslint-lsp", "stylua", "jq" },
+	automatic_installation = false,
+	handlers = {
+		shfmt = function(_, _)
+			null_ls.register(null_ls.builtins.formatting.shfmt.with({
+				extra_filetypes = { "bash", "zsh" },
+			}))
+		end,
+		prettier = function(_, _)
+			null_ls.register(null_ls.builtins.formatting.prettier.with({
+				extra_filetypes = { "astro" },
+			}))
+		end,
+		eslint = function(_, _)
+			null_ls.register(null_ls.builtins.diagnostics.eslint.with({
+				extra_filetypes = { "astro" },
+			}))
+			null_ls.register(null_ls.builtins.code_actions.eslint.with({
+				extra_filetypes = { "astro" },
+			}))
+		end,
+	},
+})