refactor(bridge): split fx bridge, stabilize VST3 host chain, drop old install engines

- remove diagnostic canaries from audio hot path (crackle fix) and
  stuck C5 note raw-MIDI test (Vst2Instrument::init noteOff)
- split native bridge into daw_vst_bridge (VSTi) + fx_vst_bridge (VST FX)
- VST3: processData prepare before setActive, zero input buses, accept
  both .vstpreset and bridge-state blob in RenderJob presets
- native_render/vst_engine: bridge-exe discovery + render_fx_chain + /fx-gui
- delete old install/ engine binaries (install via sidecar+resources now)
- add BUILD_LAYOUT.md, build_selfcheck, tools/ diagnostics

tools/patch_vectored.py

@@ -0,0 +1,39 @@
+import sys
+
+p = r"C:/Users/locpham/SonicForgeStudio/native_bridge/src/main.cpp"
+data = open(p, "rb").read()
+
+def rep(old, new, count=1):
+    global data
+    old = old.encode(); new = new.encode()
+    assert data.count(old) >= count, "pattern not found: %r" % old
+    data = data.replace(old, new, count)
+
+# 1. vectored handler ghi dump cho first-chance; cai gan CrashDumpHandler
+vectored = r"""
+// Vectored handler: catches first-chance exceptions INCLUDING heap-corruption
+// raises that never reach SetUnhandledExceptionFilter (0xC0000374 observed to
+// bypass it on this machine). Writes the same minidump then continues.
+#ifdef _WIN32
+static LONG WINAPI VectoredCrashHandler(PEXCEPTION_POINTERS ep) {
+    PEXCEPTION_RECORD er = ep ? ep->ExceptionRecord : nullptr;
+    DWORD code = er ? er->ExceptionCode : 0;
+    if (code != 0xC0000374 && code != 0xC0000005 && code != 0xC0000409) {
+        return EXCEPTION_CONTINUE_SEARCH;  // ignore benign first-chance noise
+    }
+    std::cerr << "[VCRASH] first-chance code=0x" << std::hex << code
+              << " addr=0x" << (er ? (void*)er->ExceptionAddress : nullptr)
+              << std::dec << " tid=" << GetCurrentThreadId() << std::endl;
+    // route into the same dump writer
+    return CrashDumpHandler(ep) == EXCEPTION_CONTINUE_SEARCH
+               ? EXCEPTION_CONTINUE_SEARCH
+               : EXCEPTION_CONTINUE_SEARCH;
+}
+#endif
+"""
+
+rep("int main(int argc, char* argv[]) {\n    SetUnhandledExceptionFilter(CrashDumpHandler);\n",
+    vectored + "\nint main(int argc, char* argv[]) {\n    SetUnhandledExceptionFilter(CrashDumpHandler);\n    AddVectoredExceptionHandler(1, VectoredCrashHandler);\n")
+
+open(p, "wb").write(data)
+print("patched OK, size=", len(data))