feat: cut over to WASM backend

site/tests/wasm-kill/loop.uce

@@ -0,0 +1,10 @@
+// W4 kill-test: runaway CPU. Epoch interruption traps it at the configured
+// deadline; the worker stays healthy.
+RENDER(Request& context)
+{
+	print("about to loop\n");
+	volatile u64 i = 0;
+	while(i >= 0)
+		i++;
+	print("unreachable\n");
+}

site/tests/wasm-kill/oob.uce

@@ -0,0 +1,8 @@
+// W4/W5 kill-test: explicit guest trap. Native must not run this page; the
+// wasm backend converts it into a clean UCE error page and keeps serving.
+RENDER(Request& context)
+{
+	print("about to trap\n");
+	__builtin_trap();
+	print("unreachable\n");
+}

site/tests/wasm-kill/recurse.uce

@@ -0,0 +1,14 @@
+// W4 kill-test: stack exhaustion via unbounded recursion. Traps as
+// "call stack exhausted"; the workspace drops cleanly.
+u64 wasm_kill_recurse(volatile u64 depth)
+{
+	volatile u64 next = depth + 1;
+	return(next + wasm_kill_recurse(next));
+}
+
+RENDER(Request& context)
+{
+	print("about to recurse\n");
+	volatile u64 sink = wasm_kill_recurse(0);
+	print("unreachable ", sink, "\n");
+}