Carry the colour scheme into terminals and the editor

The scheme switch already reached everything that reads
org.freedesktop.appearance -- GTK4, Qt6, Chromium, Electron -- because
ColorScheme.qml writes the gsettings key those all watch. Applications
carrying their own palettes did not follow, so choosing light mode left
the two windows actually used all day, kitty and neovim, still dark.

kitty: the 32 colours move out of kitty.conf into themes/, and kitty.conf
ends with `include current-theme.conf`. The generated file is machine
state rather than configuration, so it is gitignored and link-dotfiles
seeds it on install -- otherwise a fresh checkout starts by complaining
about a missing include. Running terminals are re-coloured in place over
their control sockets; a restart is not needed.

neovim: reads settings.json directly, since it neither watches the portal
nor keeps a socket open. Tokyo Night ships Day in the same family as
Moon, so light mode keeps the editor's identity instead of turning it
into a different-looking application. The existing readability overrides
were written against Moon and are now dark-only -- applied to Day they
would have put light grey on a light background, the same problem they
exist to fix, inverted. Light mode gets one override of its own:
tokyonight's shipped comment colour measures 2.54:1 against Day's
background, under the 3:1 floor for secondary text, so it is replaced
with 3.25:1 -- readable, still dimmer than Normal's 4.52:1.

An editor already open when the scheme flips re-applies on FocusGained,
which is cheap and fires exactly when the mismatch would be noticed.

Verified both directions: kitty re-coloured 4 live terminals, and neovim
starts as tokyonight-day with background=light and tokyonight-moon with
background=dark.

Claude-Session: https://claude.ai/code/session_01BRvzt4H8XXLPVH5MyYdk9L

config/dot/nvim/lua/config/autocmds.lua

@@ -10,3 +10,6 @@ vim.api.nvim_create_autocmd("BufWritePre", {
     vim.fn.winrestview(view)
   end,
 })
+
+-- Follow the desktop's light/dark setting while running, not only at startup.
+require("config.panama").watch()

config/dot/nvim/lua/config/panama.lua

@@ -0,0 +1,88 @@
+-- Panama desktop integration.
+--
+-- Neovim is the one application here that neither reads the desktop portal nor
+-- has a control socket open by default, so it reads the shared settings file
+-- directly -- the same ~/.config/panama/settings.json that the shell and the
+-- Hyprland config read.
+--
+-- Nothing here may raise. A missing or malformed settings file must cost the
+-- user their colour scheme preference and nothing else; editing text is more
+-- important than matching the desktop.
+
+local M = {}
+
+local function settings_path()
+  local config_home = os.getenv("XDG_CONFIG_HOME")
+  if config_home == nil or config_home == "" then
+    local home = os.getenv("HOME")
+    if home == nil or home == "" then
+      return nil
+    end
+    config_home = home .. "/.config"
+  end
+  return config_home .. "/panama/settings.json"
+end
+
+-- "dark" or "light". Defaults to dark, which is what Panama ships.
+function M.color_scheme()
+  local path = settings_path()
+  if not path then
+    return "dark"
+  end
+
+  local ok, contents = pcall(function()
+    local file = io.open(path, "r")
+    if not file then
+      return nil
+    end
+    local text = file:read("*a")
+    file:close()
+    return text
+  end)
+  if not ok or not contents or contents == "" then
+    return "dark"
+  end
+
+  local decoded_ok, decoded = pcall(vim.json.decode, contents)
+  if not decoded_ok or type(decoded) ~= "table" then
+    return "dark"
+  end
+
+  return decoded.colorScheme == "light" and "light" or "dark"
+end
+
+function M.is_light()
+  return M.color_scheme() == "light"
+end
+
+-- tokyonight ships a light variant in the same family, so light mode stays the
+-- same identity rather than becoming a different editor theme.
+function M.tokyonight_style()
+  return M.is_light() and "day" or "moon"
+end
+
+-- Re-apply the scheme when the window regains focus.
+--
+-- Neovim reads the setting once at startup and has no control socket open by
+-- default, so an editor already running when the desktop scheme flips would
+-- otherwise stay on the old palette until it was restarted. FocusGained is
+-- cheap, happens exactly when you would notice the mismatch, and does nothing
+-- at all unless the scheme actually changed.
+function M.watch()
+  local applied = M.color_scheme()
+
+  vim.api.nvim_create_autocmd("FocusGained", {
+    group = vim.api.nvim_create_augroup("PanamaColorScheme", { clear = true }),
+    callback = function()
+      local current = M.color_scheme()
+      if current == applied then
+        return
+      end
+      applied = current
+      vim.o.background = current
+      pcall(vim.cmd.colorscheme, current == "light" and "tokyonight-day" or "tokyonight-moon")
+    end,
+  })
+end
+
+return M