feat: scaffold FCES-native C++ project with libtorch integration

- CMakeLists.txt with libtorch, GoogleTest, GoogleBenchmark, OpenMP, pybind11
- Header files: config, controller, population, fitness, evolution, spectral, oscillation, telemetry, optimizer
- Source implementations: controller (full micro-MLP forward pass, mutation, crossover), fitness (Welford's algorithm), oscillation (DFT), spectral (SVD rank), optimizer (sign-SGD stub)
- Tests: controller, population, fitness, optimizer (Google Test)
- Benchmarks: evolve throughput, optimizer step (Google Benchmark)
- Examples: simple optimization, PyTorch/libtorch integration
- Python extension: pybind11 bindings with setup.py
- README with architecture diagram and build instructions

tests/test_population.cpp

@@ -0,0 +1,28 @@
+#include <gtest/gtest.h>
+#include "fces/population.hpp"
+
+using namespace fces;
+
+TEST(PopulationTest, Construction) {
+    Population pop(50);
+    EXPECT_EQ(pop.size(), 50);
+}
+
+TEST(PopulationTest, DirectConstruction) {
+    Population pop(200, 10000, EliteStrategy::Cumulative,
+                   false, false, false, false, false, true);
+    EXPECT_EQ(pop.size(), 1);
+}
+
+TEST(PopulationTest, GetBestActive) {
+    Population pop(10);
+    auto& best = pop.get_best_active();
+    // Should not crash
+    EXPECT_GE(best.id, 0u);
+}
+
+TEST(PopulationTest, CalmDown) {
+    Population pop(10);
+    pop.calm_down();
+    EXPECT_LT(pop.global_sigma_modifier(), 1.0f);
+}