feat: percentage-based container sizing with live boundary resize

- Add _splitRatios[] to WindowContainer — each child owns a fraction of
  the parent that always sums to 1.0; bounds are computed via prefix-sum
  so the last item absorbs rounding remainder (no pixel gaps)
- addWindow/removeWindow reset to equal splits; itemDragged swaps only
  items (ratios stay slot-based) so windows take the size of the slot
  they move into
- Add adjustBoundary() for live edge-drag resizing clamped to a
  configurable minimum (default 10%, schema key min-window-size-percent)
- Add reset-ratios keybinding (Ctrl+Z) that resets the active container
  to equal splits via WindowManager.resetActiveContainerRatios()
- Connect size-changed signal alongside position-changed so east/south
  edge drags (width-only changes) are detected and the adjacent window
  is repositioned live
- Replace LIFO pop() event queue with name-keyed Map so duplicate events
  collapse to the latest callback and timers never fight each other
- Remove redundant move_frame() before move_resize_frame(); fix retry
  condition to use symmetric pixel tolerance
- Add _isTiling re-entrancy guard around all tileWindows() call sites
  so compositor position-changed callbacks cannot recurse
- Remove double tileWindows() call in monitor.tileWindows() (move()
  already calls it internally)

schemas/org.gnome.shell.extensions.aerospike.gschema.xml

@@ -49,5 +49,18 @@
             <description>Toggles the orientation of the container holding the active window between horizontal and vertical</description>
         </key>
 
+        <key name="reset-ratios" type="as">
+            <default><![CDATA[['<Primary>z']]]></default>
+            <summary>Reset container ratios to equal splits</summary>
+            <description>Resets all window size ratios in the active window's container to equal splits</description>
+        </key>
+
+        <key name="min-window-size-percent" type="d">
+            <default>0.10</default>
+            <range min="0.01" max="0.49"/>
+            <summary>Minimum window size percentage</summary>
+            <description>Minimum fraction of a container that any single window may occupy when resizing boundaries</description>
+        </key>
+
     </schema>
 </schemalist>