refactor(2meet-data-optimizer-hivepress-addon): stop registering Hot zone fields

- ADR-003 step 4 (AddOn side): core, requests, bookings, memberships and
  marketplace adapters no longer register zone=hot fields or contribute
  hot_* FSM modules; their keys live in TMDO_HivePress_Entity_Groups.
  Cold/warm registrations are unchanged.
- Hot-table doctor probes go with them (trait defaults apply). The
  hot-clause query rewrite and cron optimizer are now inert and are left
  for the ADR step-5 removal together with core's hot path.
- New NoHotZoneRegistrationTest pins the invariant across all 13 adapters;
  per-adapter hot assertions removed.
- Verify: HP unit 142 / integration 49 green, phpcs clean (WordPress)
- PR: PR-037

tests/unit/RequestsAdapterTest.php

@@ -35,19 +35,6 @@ class HivePressRequestsAdapterTest extends TestCase {
 		$this->assertSame( 'hp_offer', WPDO_HivePress_Requests_Adapter::OFFER_COMMENT_TYPE );
 	}
 
-	public function test_on_register_fields_registers_request_hot_columns(): void {
-		$registry = WPDO_Schema_Registry::instance();
-		$this->adapter->on_register_fields( $registry );
-
-		$drafted = $registry->get_field( 'hp_request', 'hp_drafted' );
-		$this->assertSame( 'hot', $drafted['zone'] );
-		$this->assertTrue( (bool) $drafted['indexed'] );
-
-		$expired = $registry->get_field( 'hp_request', 'hp_expired_time' );
-		$this->assertSame( 'hot', $expired['zone'] );
-		$this->assertTrue( (bool) $expired['indexed'] );
-	}
-
 	public function test_registers_no_offer_shadow_table(): void {
 		// The offer shadow table was never created, so every mirror write failed.
 		$registry = WPDO_Custom_Table_Registry::instance();
@@ -69,8 +56,4 @@ class HivePressRequestsAdapterTest extends TestCase {
 	public function test_score_aggregates_to_perfect_ten(): void {
 		$this->assertSame( 10.0, $this->adapter->suitability_score()['aggregate'] );
 	}
-
-	public function test_migrations_lists_only_request_hot_module(): void {
-		$this->assertSame( array( 'hot_hp_request' ), $this->adapter->migrations() );
-	}
 }