Add experimental preset L and fix DLSS resource lifetimes and waits

- Build L texture variants and complete older release kernel bundles.
- Add selective Swin encoder fallback to reduce L/M motion trails.
- Add opt-in GPU motion-vector dilation for thin geometry and sky gaps.
- Replace GPU input waits with cancellable readiness polling and use
  sleeping event queries for completion.
- Retain recorded resources through command allocator completion, defer
  shutdown until cleanup, and preserve unfinished output synchronization.
- Extend lifecycle harness checks and add event, model and motion tests.
- Update configuration defaults, build scripts and release documentation.

tests/test_event_wait.py

@@ -0,0 +1,36 @@
+"""Completion/error contracts for the sleeping CUDA event wait (no GPU needed)."""
+from pathlib import Path
+import subprocess
+import tempfile
+import unittest
+
+ROOT = Path(__file__).resolve().parents[1]
+
+
+class EventWaitTests(unittest.TestCase):
+    def test_completion_pending_and_error(self):
+        source = r'''
+#include "d4r_event_wait.h"
+#include <cassert>
+int main() {
+    int sleeps = 0, queries = 0;
+    assert(d4r_wait_event([] { return 0; }, [&] { ++sleeps; }) == 0);
+    assert(sleeps == 0);
+    assert(d4r_wait_event([&] { return ++queries <= 7 ? 600 : 0; },
+                         [&] { ++sleeps; }) == 0);
+    assert(queries == 8 && sleeps == 7);
+    sleeps = 0;
+    assert(d4r_wait_event([] { return 719; }, [&] { ++sleeps; }) == 719);
+    assert(sleeps == 0);
+    queries = 0;
+    assert(d4r_wait_event([&] { return ++queries == 1 ? 600 : 700; },
+                         [&] { ++sleeps; }) == 700);
+    assert(sleeps == 1);
+}
+'''
+        with tempfile.TemporaryDirectory() as tmp:
+            runner = Path(tmp) / "wait"
+            subprocess.run(["c++", "-x", "c++", "-std=c++17", "-Wall", "-Wextra", "-Werror",
+                            "-I", str(ROOT / "tools"), "-o", str(runner), "-"],
+                           input=source, text=True, check=True, capture_output=True)
+            subprocess.run([str(runner)], check=True, timeout=5)