nvim: fix startup errors, add language + project-run support

Startup errors:
- catppuccin: the bufferline integration moved to catppuccin.special.bufferline
- lspconfig-extended: drop the removed LazyVim keymaps API for
  opts.servers["*"].keys, and move remove-workspace-folder to <leader>clR
  so it stops colliding with LspRestart on <leader>clr
- options: lazyvim_cmp = "blink" is not a valid value, it is "blink.cmp"

Language support (python, c/cpp, rust, zephyr, and the common ones) via
lazyvim.json extras: dap.core, clangd, cmake, docker, git, json, rust,
toml, yaml.

- lang/zephyr.lua: gated entirely on ZEPHYR_BASE / ZEPHYR_SDK_INSTALL_DIR /
  GNUARMEMB_TOOLCHAIN_PATH, returning {} when none are set, so it is inert
  on machines without Zephyr. Nothing is hardcoded: the clangd
  --query-driver globs are built from those vars, falling back to resolving
  the cross-gcc through exepath()+fs_realpath(). Adds devicetree/kconfig
  treesitter and filetypes (*.overlay, Kconfig.*, prj.conf, *_defconfig).
- clangd/config.yaml: strip the GCC-only flags Zephyr emits into
  compile_commands.json (-fno-printf-return-value, -mfp16-format=*, ...),
  which clang rejects as "Unknown argument". Remove only drops flags that
  are present, so it is a no-op for native builds. Takes a built Zephyr app
  from 15 diagnostics to 0, with CONFIG_* resolving into the generated
  autoconf.h.
- npm-servers.lua: npm is not installed here, so yaml/docker servers failed
  to install on every startup and to spawn on every matching file. Sets
  both enabled = false and mason = false for servers whose binary is
  missing from PATH and from mason/bin.

Project runner under <leader>R (<leader>r is refactoring), dispatching on
the detected project type -- zephyr, rust, python, cmake, make:

  Rr run project   Rb build   Rt test   RF build+flash   Rf run file
  Rk configure     Rc clean   Rs select target/board     Ri info

Zephyr boards are picked with vim.ui.select over `west boards`, cached per
scan and persisted per project root under stdpath("state"), never written
into the project. A build with no board set prompts first, then proceeds.
Detection walks up from the last real file buffer, tracked by an autocmd,
because a terminal opened by one of these verbs would otherwise become the
buffer detection ran from.

Also <leader>b1..b9/b0 jump to buffer N (ordinal, no longer skipping the
current one) and <leader>b<Left>/<Right> cycle.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01StGBghPW9Dm7z7uj2VNWHr

nvim/lua/plugins/extras/ui/bufferline-extended.lua

@@ -8,6 +8,21 @@ table.insert(keys, { prefix .. "s", "<Cmd>BufferLineSortByExtension<CR>", desc =
 
 table.insert(keys, { prefix .. "<", "<cmd>BufferLineMovePrev<cr>", desc = "Move buffer prev" })
 table.insert(keys, { prefix .. ">", "<cmd>BufferLineMoveNext<cr>", desc = "Move buffer next" })
+
+-- Jump straight to a buffer by its position in the bufferline.
+-- BufferLineGoToBuffer takes the absolute 1-based slot, so <leader>b1 is always
+-- the leftmost buffer and the count never skips the one you are already on.
+-- The ordinal shown in the bufferline (see numbers = "ordinal" below) is the
+-- number to press.
+for i = 1, 9 do
+  table.insert(keys, { prefix .. i, "<cmd>BufferLineGoToBuffer " .. i .. "<cr>", desc = "Buffer " .. i })
+end
+-- ...and 0 for the last one, however many there are.
+table.insert(keys, { prefix .. "0", "<cmd>BufferLineGoToBuffer -1<cr>", desc = "Last Buffer" })
+
+-- Arrows step through the bufferline in visible order.
+table.insert(keys, { prefix .. "<Left>",  "<cmd>BufferLineCyclePrev<cr>", desc = "Prev Buffer" })
+table.insert(keys, { prefix .. "<Right>", "<cmd>BufferLineCycleNext<cr>", desc = "Next Buffer" })
 -- stylua: ignore end
 
 return {
@@ -15,9 +30,11 @@ return {
   keys = keys,
   opts = {
     options = {
-      modified_icon = "",
+      modified_icon = "",
       color_icons = true,
       separator_style = "slope",
+      -- Show 1, 2, 3 ... so the number you see is the number you press.
+      numbers = "ordinal",
     },
   },
 }