Clean up the hand-registered test type after the expectation

PredicateConstructionThrowsWhenNoMemberMatches manually inserted a
MismatchedRecord entry into the process-wide reflection registry (with no
member metadata, to force an offset-match miss) but never removed it. Left
in place, Database::Database iterates every registered record on
Initialize() and would generate "CREATE TABLE IF NOT EXISTS
MismatchedRecord ();" (empty column list) for it - invalid SQL that throws
and breaks every later Database::Initialize() call in the same test binary,
depending on test execution order.

This didn't surface in a normal sequential run, but reliably broke under
--gtest_shuffle: 4 of 5 random seeds failed with 6-37 cascading test
failures before this fix, and all of 10 random seeds pass after it. Added a
small RAII ScopedRegistryCleanup that erases the hand-inserted entry on
scope exit.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NUt3c1wdseRtRSSXfg3MCK

Author: claude

tests/query_predicates_test.cc

@@ -24,6 +24,9 @@
 
 #include <gtest/gtest.h>
 
+#include <string>
+#include <utility>
+
 #include "person.h"
 #include "pet.h"
 
@@ -223,6 +226,22 @@ struct MismatchedRecord {
     int64_t id;
     int64_t value;
 };
+
+// Erases a hand-inserted entry from the process-wide reflection registry on scope exit. Without
+// this, a MismatchedRecord-shaped entry with no member metadata would linger in the registry for
+// the rest of the test binary: Database::Database iterates every registered record and would
+// generate "CREATE TABLE IF NOT EXISTS MismatchedRecord ();" (empty column list) for it, failing
+// every later Database::Initialize() call in this process.
+class ScopedRegistryCleanup {
+public:
+    explicit ScopedRegistryCleanup(std::string type_id) : type_id_(std::move(type_id)) {}
+    ~ScopedRegistryCleanup() {
+        GetReflectionRegisterInstance()->records.erase(type_id_);
+    }
+
+private:
+    std::string type_id_;
+};
 }  // namespace
 
 TEST(QueryPredicatesTest, PredicateConstructionThrowsForUnregisteredType) {
@@ -237,8 +256,10 @@ TEST(QueryPredicatesTest, PredicateConstructionThrowsWhenNoMemberMatches) {
     // pointer-to-member (here because the type was registered by hand with no members at all,
     // rather than via the FIELDS macro), the QueryPredicate constructor must fail fast instead
     // of silently leaving member_name_ empty and emitting malformed SQL like " = ?"
+    const std::string type_id = typeid(MismatchedRecord).name();
     auto& instance = *GetReflectionRegisterInstance();
-    instance.records[typeid(MismatchedRecord).name()].name = "MismatchedRecord";
+    instance.records[type_id].name = "MismatchedRecord";
+    const ScopedRegistryCleanup cleanup(type_id);
 
     EXPECT_THROW(Equal(&MismatchedRecord::value, 42), std::runtime_error);
 }