feat(kde): open ghostty windows fullscreen instead of at a fixed size

.claude/skills/kde-config/lessons/window-rules.md

@@ -51,9 +51,28 @@ All from `src/rules.h`:
 | `sizerule`, `positionrule`, … (`*rule` for set-type properties) | `Rules::SetRule` (anonymous base enum) | 0 Unused, 1 DontAffect, 2 Force, 3 Apply ("Apply initially"), 4 Remember, 5 ApplyNow, 6 ForceTemporarily |
 | `types` | `NET::WindowTypeMask` bitmask (`/usr/include/KF6/KWindowSystem/netwm_def.h`) | 1 Normal, default `AllTypesMask` (all bits) |
 | `wmclasscomplete` | Bool | `true` = match whole window class |
+| `fullscreen`, `maximizevert`, `maximizehoriz` | Bool (`src/rulesettings.kcfg`) | `true` + a `*rule` companion (`fullscreenrule`, `maximizevertrule`, `maximizehorizrule`) |
 
 `size` is a `QSize` serialised as `width,height`.
 
+## Initial-state order for a new window
+
+`XdgToplevelWindow::initialize()` (`src/xdgshellwindow.cpp`) applies the
+`Apply` rules in a fixed order: position and size first, then maximize,
+then fullscreen, then activities, desktops, and the rest. A fullscreen
+rule therefore wins over a size rule at mapping time; the size only
+matters again if the window later leaves fullscreen. Fullscreen and
+maximized are distinct properties: fullscreen hides the panel and the
+title bar, maximized keeps both.
+
+## Retiring a property
+
+`ini_file` only writes the keys it is given, so dropping a property from
+`kde_window_rules` leaves the old key on every machine that already had
+it. Set the property to `null` instead: the rule task then removes the
+key (`state: absent`), with real change detection under `--check`. Keep
+the null entry until every machine has converged, then delete it.
+
 ## "Detect Window Properties" leaves inert keys behind
 
 The KCM's property detector copies the window's title into `title=` even

roles/kde/defaults/main.yml

@@ -47,16 +47,19 @@ kde_panel_layout_file: "{{ ansible_facts.env.HOME }}/.local/share/hanzo/panel-la
 # enums: *match is Rules::StringMatch (1 = exact), *rule is
 # Rules::SetRule (3 = apply initially), types is a NET::WindowTypeMask
 # bitmask (1 = normal window). Booleans are quoted: KConfig reads
-# lowercase true|false.
+# lowercase true|false. A null value removes the key from the group:
+# that is how a property Hanzo once wrote is retired on every machine.
 kde_window_rules:
   hanzo-ghostty:
     Description: Window settings for com.mitchellh.ghostty
     wmclass: ghostty com.mitchellh.ghostty
     wmclasscomplete: "true"
     wmclassmatch: 1
     types: 1
-    size: 1600,1001
-    sizerule: 3
+    fullscreen: "true"
+    fullscreenrule: 3
+    size: ~
+    sizerule: ~
 
 # Session restore at login. One of restorePreviousLogout,
 # restoreSavedSession, emptySession — the ksmserver loginMode names.

roles/kde/tasks/window-rule.yml

@@ -1,13 +1,15 @@
 ---
 # One kwinrulesrc group per rule. kde_window_rule is the {key: group,
-# value: properties} item supplied by the including loop.
+# value: properties} item supplied by the including loop. A property
+# with a null value is removed from the group instead of written.
 
 - name: Write window rule {{ kde_window_rule.key }}
   community.general.ini_file:
     path: "{{ ansible_facts.env.HOME }}/.config/kwinrulesrc"
     section: "{{ kde_window_rule.key }}"
     option: "{{ item.key }}"
     value: "{{ item.value }}"
+    state: "{{ 'absent' if item.value is none else 'present' }}"
     no_extra_spaces: true
     mode: "0644"
   loop: "{{ kde_window_rule.value | dict2items }}"