fix(ui): #139 sheets size themselves; #141 waybar clicks stop reading the env

#139 — calcurse/doctor floated full-screen. Two faults stacked, which is
why it looked like the float rules were dead:
  1. Hyprland 0.55.4 silently ignores percentage `size` rules. Matrix on
     hardware (both orders, kitty memory off): `size 60% 65%` never
     applies, `size 1536 936` applies either way, configerrors empty both
     times. Rule order was a red herring.
  2. Kitty defaults to remember_window_size=yes and replays the last OS
     window's size into every float — so after a tiled terminal, a sheet
     opens maximized. This is the Ghostty regression: Ghostty had no such
     memory, so fault 1 stayed invisible until #95.

Fix: remember_window_size=no (floats must be deterministic) and the sheets
ask for their own size — term-sheet.nix reads the focused monitor and
hands kitty the px, because px in a rule cannot mean "a fraction of *this*
screen" and one pair cannot serve 2560x1440 and the 1366x768 Acer (#131).
Those windows keep float/center and deliberately carry no size rule.

#141 — the updates click did nothing: whole-swaps hand-wrote
`sh -c '$TERMINAL …'` and Waybar has no TERMINAL (home.sessionVariables →
login shells only; the bar is spawned by Hyprland). Fixed at the root:
`nomarchy-updates upgrade-window` opens its own window, so all five call
sites name one env-free command and a theme file stops having an opinion
about terminals. checks.waybar-swap-env guards the class.

Bernardo asked mid-task for the update window to float — it is now the
third caller of the sheet helper (com.nomarchy.updates, 45%x50%).

V3 on the dev box: calendar 1536x936, doctor 1408x1008, updates 1152x720
— exactly the intended fractions, floating and centred; #141 driven under
`env -i` with no TERMINAL, matching Waybar's real environment; the guard
proven by reintroducing the bug. Acer V3 queued.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

modules/home/waybar.nix

@@ -11,6 +11,7 @@
 
 let
   t = config.nomarchy.theme;
+  termSheet = import ./term-sheet.nix { inherit pkgs; };
 
   # Whether the keyboard-layout indicator is worth bar space, and the filter
   # that holds a whole-swap to the same answer. Contract + rationale (and
@@ -95,13 +96,14 @@ let
 
   # Opens calcurse (lightweight TUI calendar) in a floating, centered kitty
   # window — Waybar clock on-click. Distinct --class → hyprland.nix float
-  # rules. Kitty is always installed (kitty.nix).
+  # rules. Kitty is always installed (kitty.nix). The sheet sizes itself
+  # (#139: a percentage `size` rule is silently ignored) — see term-sheet.nix.
   calendarLauncher = pkgs.writeShellScriptBin "nomarchy-calendar" ''
     if ! command -v calcurse >/dev/null 2>&1; then
       notify-send "Calendar" "calcurse isn't installed (removed from home.packages?)." 2>/dev/null
       exit 0
     fi
-    exec kitty --class=com.nomarchy.calendar -e calcurse
+    exec ${termSheet}/bin/nomarchy-term-sheet com.nomarchy.calendar 60 65 calcurse
   '';
 
   # VPN indicator — shows a shield when a NetworkManager VPN/WireGuard
@@ -353,7 +355,7 @@ let
       return-type = "json";
       interval = 1800;
       signal = 9;
-      on-click = "${config.nomarchy.terminal} -e nomarchy-updates upgrade";
+      on-click = "nomarchy-updates upgrade-window";
     };
 
     # swaync notification bell + Do-Not-Disturb state. `-swb` streams JSON