fix(electrobun): GTK FFI direct resize via gtk_window_resize/move

Electrobun's setSize respects WebView min-size constraint. Bypass it
with direct gtk_window_resize() + gtk_window_move() FFI calls.
clearMinSizeTree() runs on every resize frame to suppress WebView
re-propagation. gtkSetFrame() exported as new RPC endpoint.

ui-electrobun/src/bun/gtk-window.ts

@@ -49,6 +49,14 @@ function getGtk() {
         args: [FFIType.ptr, FFIType.ptr, FFIType.ptr, FFIType.i32],
         returns: FFIType.void,
       },
+      gtk_window_resize: {
+        args: [FFIType.ptr, FFIType.i32, FFIType.i32],
+        returns: FFIType.void,
+      },
+      gtk_window_move: {
+        args: [FFIType.ptr, FFIType.i32, FFIType.i32],
+        returns: FFIType.void,
+      },
       // Container traversal
       gtk_bin_get_child: {
         args: [FFIType.ptr],
@@ -247,6 +255,28 @@ export function beginMoveDrag(
   }
 }
 
+/**
+ * Direct GTK resize — bypasses Electrobun's setSize which respects WebView min-size.
+ * Clears min-size tree first, then calls gtk_window_resize + gtk_window_move.
+ */
+export function gtkSetFrame(
+  windowPtr: number | bigint,
+  x: number, y: number, width: number, height: number,
+) {
+  const lib = getGtk();
+  if (!lib) return false;
+  try {
+    // Clear min-size on every frame update during resize
+    clearMinSizeTree(lib, windowPtr as any);
+    lib.symbols.gtk_window_resize(windowPtr as any, Math.max(400, Math.round(width)), Math.max(300, Math.round(height)));
+    lib.symbols.gtk_window_move(windowPtr as any, Math.round(x), Math.round(y));
+    return true;
+  } catch (err) {
+    console.error("[gtk-window] gtkSetFrame failed:", err);
+    return false;
+  }
+}
+
 // Edge string → GDK_EDGE mapping
 const EDGE_MAP: Record<string, GdkEdge> = {
   n: GDK_EDGE.N, s: GDK_EDGE.S, e: GDK_EDGE.E, w: GDK_EDGE.W,

ui-electrobun/src/bun/index.ts

@@ -154,6 +154,13 @@ const rpc = BrowserView.defineRPC<PtyRPCSchema>({
           return { ok: true };
         } catch (err) { console.error("[window.clearMinSize]", err); return { ok: false }; }
       },
+      "window.gtkSetFrame": ({ x, y, width, height }: { x: number; y: number; width: number; height: number }) => {
+        try {
+          const { gtkSetFrame } = require("./gtk-window.ts");
+          const ok = gtkSetFrame((mainWindow as any).ptr, x, y, width, height);
+          return { ok };
+        } catch (err) { console.error("[window.gtkSetFrame]", err); return { ok: false }; }
+      },
     },
     messages: {},
   },

ui-electrobun/src/mainview/App.svelte

@@ -148,7 +148,8 @@
     if (resizeEdge.includes('s')) height = Math.max(MIN_H, height + dy);
     if (resizeEdge.includes('n')) { const nh = Math.max(MIN_H, height - dy); y += height - nh; height = nh; }
 
-    appRpc.request['window.setFrame']({ x: Math.round(x), y: Math.round(y), width: Math.round(width), height: Math.round(height) }).catch(() => {});
+    // Use GTK FFI directly — bypasses Electrobun's setSize which respects WebView min-size
+    appRpc.request['window.gtkSetFrame']({ x: Math.round(x), y: Math.round(y), width: Math.round(width), height: Math.round(height) }).catch(() => {});
   }
 
   function onResizeEnd() {