test(ha-config-bootstrap): RED phase tests for quorum election logic (task 4.1)

- 21 test functions covering all 12 acceptance criteria (req 2.1-2.12)
- Tests: 2/3 quorum wins, 1/3 loses, voted_for enforcement, freshness gate,
  single-node self-elects, split-vote retry, in_catch_up denial, jitter
- Build fails with undefined reference to handle_request_vote,
  ha_elect_evaluate_and_signal, am_i_primary_quorum (expected RED proof)

src/controller/testsuite/controller_test.c

@@ -35,6 +35,7 @@ extern void test_ctrl_metrics(void);
 extern void test_config_repl(void);
 extern void test_worker_join(void);
 extern void test_ha_startup(void);
+extern void test_ha_election(void);
 
 void setUp(void) { return; }
 
@@ -139,6 +140,7 @@ int main(int argc, char* argv[])
     TEST(test_config_repl);
     TEST(test_worker_join);
     TEST(test_ha_startup);
+    TEST(test_ha_election);
 
     return UNITY_END();
 }