Step 150: add Rust parser and generator

editor/tests/step150_test.cpp

@@ -0,0 +1,63 @@
+// Step 150 TDD Test: Rust CST-to-AST + generator
+#include "ast/Parser.h"
+#include "ast/Generator.h"
+#include <iostream>
+
+static void expect(bool cond, const std::string& name, int& passed, int& failed) {
+    if (cond) {
+        std::cout << "Test " << (passed + failed + 1) << " PASS: " << name << "\n";
+        ++passed;
+    } else {
+        std::cout << "Test " << (passed + failed + 1) << " FAIL: " << name << "\n";
+        ++failed;
+    }
+}
+
+int main() {
+    int passed = 0;
+    int failed = 0;
+
+    std::string rust = R"(
+use std::collections::HashMap;
+
+struct Boxy { value: i32 }
+
+impl Boxy {
+  fn size(&self, n: i32) -> i32 { return n + 1; }
+}
+
+fn add(a: i32, b: i32) -> i32 {
+  let c = a + b;
+  return c;
+}
+)";
+
+    auto mod = TreeSitterParser::parseRust(rust);
+    expect(mod != nullptr, "rust module created", passed, failed);
+    auto funcs = mod->getChildren("functions");
+    expect(funcs.size() >= 2, "rust functions discovered", passed, failed);
+
+    bool foundAdd = false;
+    bool foundImpl = false;
+    for (const auto* fnNode : funcs) {
+        if (fnNode->conceptType != "Function") continue;
+        auto* fn = static_cast<const Function*>(fnNode);
+        if (fn->name == "add") foundAdd = true;
+        if (fn->name == "Boxy.size") foundImpl = true;
+    }
+    expect(foundAdd, "rust top-level function name", passed, failed);
+    expect(foundImpl, "rust impl method name", passed, failed);
+
+    RustGenerator gen;
+    std::string out = gen.generate(mod.get());
+    expect(out.find("use std::collections::HashMap;") != std::string::npos,
+           "rust imports generated", passed, failed);
+    expect(out.find("fn add") != std::string::npos,
+           "rust function signature generated", passed, failed);
+    expect(out.find("impl Boxy") != std::string::npos,
+           "rust impl block generated", passed, failed);
+
+    std::cout << "\n=== Step 150 Results: " << passed << " passed, "
+              << failed << " failed ===\n";
+    return failed == 0 ? 0 : 1;
+}