refactor(nvim,zsh): remove Mason; use Home-Manager-provisioned tooling

LSPs, formatters, linters, and the lldb-dap debugger now come from
~/.nix-profile/bin (see nix/common.nix). lspconfig keeps the default
configs; we just opt-in via vim.lsp.enable() with an explicit list.

Changes:
  - dot_config/nvim/lua/plugins/lsp.lua: drop mason*, replace
    mason-lspconfig handler with explicit vim.lsp.enable({...}); drop
    groovy/jenkins formatters and lint entries; drop systemd lint
    (nginx + groovy + systemdlint tools dropped per plan).
  - dot_config/nvim/lua/plugins/debug.lua: drop mason-nvim-dap; drop
    codelldb adapter; switch dap.configurations.cpp to type='lldb'
    (lldb-dap is the upstream successor, ships with pkgs.lldb).
  - dot_config/nvim/init.lua: remove mason.nvim, mason-lspconfig.nvim,
    mason-tool-installer.nvim, mason-nvim-dap.nvim from vim.pack.add.
  - dot_config/nvim/lua/config/update.lua: remove MasonToolsUpdateSync.
  - dot_config/zsh/dot_zshrc: flip plugin source order — prefer
    ~/.nix-profile/share, fall back to /usr/share/zsh (was the other
    way around).
  - nix/bootstrap.sh: drop the uv-python3.11 step (no longer needed
    once Mason no longer source-builds Python LSPs on Ubuntu 20.04).

Phase 6 of the nix-on-host migration plan.

1 files changed, 2 insertions, 31 deletions

diff --git a/nix/bootstrap.sh b/nix/bootstrap.sh
index 9f5e144..86f82ca 100755
--- a/nix/bootstrap.sh
+++ b/nix/bootstrap.sh
@@ -8,8 +8,7 @@
 #   1. Install Nix (Determinate Systems installer, multi-user).
 #   2. Clone (or fast-forward) the dotfiles repo to ~/.local/share/dotfiles.
 #   3. Run `home-manager switch --flake .../nix#vm`.
-#   4. Install python3.11 via `uv` (needed by Mason pip installs).
-#   5. Add Nix-store zsh to /etc/shells and chsh the user.
+#   4. Add Nix-store zsh to /etc/shells and chsh the user.
 #
 # Environment overrides:
 #   DOTFILES_REPO   Git URL (default: https://github.com/ruifm/dotfiles)
@@ -35,9 +34,6 @@ else
   log "Nix already installed, skipping installer."
 fi
 
-# ── 1b. (moved to step 4 — uv comes from the nix profile, only available
-#         after `home-manager switch`) ─────────────────────────────────────────
-
 # Source nix env for the rest of this script (installer writes
 # /etc/profile.d/nix.sh but the current shell hasn't sourced it).
 if [ -f /nix/var/nix/profiles/default/etc/profile.d/nix-daemon.sh ]; then
@@ -68,32 +64,7 @@ nix --extra-experimental-features 'nix-command flakes' \
   run home-manager/master -- \
   switch --impure --flake "$DIR/nix#vm" -b backup
 
-# ── 4. Mason's python interpreter (via uv from the nix profile) ──────────────
-# Mason installs some LSPs/linters into per-package pip venvs. We need a
-# python3.11 that:
-#   (a) meets Mason's >=3.10 version requirement (Ubuntu 20.04 ships
-#       /usr/bin/python3 = 3.8 — too old), and
-#   (b) accepts manylinux wheels (Nix's python rejects them by design;
-#       pip then falls back to compiling `nodejs-wheel-binaries` from
-#       source, which fails on the host's gcc 9.4 — needs C++20).
-#
-# `uv python install 3.11` fetches a portable CPython build (python-build-
-# standalone, manylinux-compatible) into ~/.local/share/uv/python/. We
-# symlink its `python3.11` into ~/.local/bin/ (already on PATH from
-# zprofile) so Mason discovers it. Does NOT shadow /usr/bin/python3 —
-# leaf-tools policy intact. Works on any distro/release, no PPA required.
-UV_BIN="$HOME/.nix-profile/bin/uv"
-if [ -x "$UV_BIN" ]; then
-  if [ ! -x "$HOME/.local/bin/python3.11" ]; then
-    log "Installing python3.11 via uv (required for Mason pip installs)…"
-    "$UV_BIN" python install 3.11
-    UV_PY311="$("$UV_BIN" python find 3.11)"
-    mkdir -p "$HOME/.local/bin"
-    ln -sf "$UV_PY311" "$HOME/.local/bin/python3.11"
-  fi
-fi
-
-# ── 5. chsh to nix-store zsh ─────────────────────────────────────────────────
+# ── 4. chsh to nix-store zsh ─────────────────────────────────────────────────
 NIX_ZSH="$HOME/.nix-profile/bin/zsh"
 if [ -x "$NIX_ZSH" ]; then
   if ! grep -qxF "$NIX_ZSH" /etc/shells 2>/dev/null; then