fix: LayoutToggle silent no-op when parent is not HSPLIT/VSPLIT

[mayconrcmello]

Summary

LayoutToggle (the action behind con-split-layout-toggle, default Super+G) only swaps between HSPLIT and VSPLIT. Every other parent layout (TABBED, STACKED, or the bare MONITOR container) hits the implicit fallthrough and the action is a silent no-op — same shortcut, no feedback, no error.

Reproducible case

Three windows side-by-side where Forge nested them as:

HSPLIT
├── W1
└── HSPLIT-or-TABBED
    ├── W2
    └── W3

• Focus W1 → parent = outer HSPLIT → Super+G works.
• Focus W3 → parent = inner HSPLIT-or-VSPLIT → Super+G works.
• Focus W2 with the inner container in tabbed mode → parent = TABBED → Super+G silently does nothing.

Reported on a multi-monitor setup as "the middle window won't toggle."

Fix

Fall back to determineSplitLayout() (which returns HSPLIT or VSPLIT depending on monitor orientation) when the current layout is anything other than a split. The binding then always has a visible effect — toggling out of tabbed/stacked/monitor mode into a sensible split.

       case "LayoutToggle":
         if (!focusNodeWindow) return;
         currentLayout = focusNodeWindow.parentNode.layout;
         if (currentLayout === LAYOUT_TYPES.HSPLIT) {
           focusNodeWindow.parentNode.layout = LAYOUT_TYPES.VSPLIT;
         } else if (currentLayout === LAYOUT_TYPES.VSPLIT) {
           focusNodeWindow.parentNode.layout = LAYOUT_TYPES.HSPLIT;
+        } else {
+          focusNodeWindow.parentNode.layout = this.determineSplitLayout();
         }

Test plan

• node --check
• In a workspace with 3 windows where the middle pair is in a tabbed container, focus the middle window and press Super+G → container becomes HSPLIT/VSPLIT.
• In an HSPLIT container, Super+G still toggles to VSPLIT (and vice-versa), no regression.