LibWasm: Add basic support for module instantiation and execution stubs

This adds very basic support for module instantiation/allocation, as
well as a stub for an interpreter (and executions APIs).
The 'wasm' utility is further expanded to instantiate, and attempt
executing the first non-imported function in the module.
Note that as the execution is a stub, the expected result is a zero.
Regardless, this will allow future commits to implement the JS
WebAssembly API. :^)

Userland/Libraries/LibWasm/AbstractMachine/Configuration.h

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2021, Ali Mohammad Pur <mpfard@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibWasm/AbstractMachine/AbstractMachine.h>
+
+namespace Wasm {
+
+typedef u64 (*HostFunctionType)(Store&, Vector<Value>&);
+
+class Configuration {
+public:
+    explicit Configuration(Store& store)
+        : m_store(store)
+    {
+    }
+
+    Optional<Label> nth_label(size_t);
+    void set_frame(NonnullOwnPtr<Frame> frame)
+    {
+        m_current_frame = frame.ptr();
+        m_stack.push(move(frame));
+        m_stack.push(make<Label>(m_current_frame->expression().instructions().size() - 1));
+    }
+    auto& frame() const { return m_current_frame; }
+    auto& frame() { return m_current_frame; }
+    auto& ip() const { return m_ip; }
+    auto& ip() { return m_ip; }
+    auto& depth() const { return m_depth; }
+    auto& depth() { return m_depth; }
+    auto& stack() const { return m_stack; }
+    auto& stack() { return m_stack; }
+
+    Result call(FunctionAddress, Vector<Value> arguments);
+    Result execute();
+
+private:
+    Store& m_store;
+    Frame* m_current_frame { nullptr };
+    Stack m_stack;
+    size_t m_depth { 0 };
+    InstructionPointer m_ip;
+};
+
+}