test(integration): add multitenant ORE ordering tests for all tenant keysets

Generate 54 tests (18 per tenant × 3 keysets) covering text ASC/DESC,
NULLs, qualified columns, aliases, projection, plaintext, mixed columns,
simple protocol, and numeric types (int2/int4/int8/float8 ASC/DESC).
Uses a macro to generate per-tenant submodules without extra dependencies.

Author: tobyhede

packages/cipherstash-proxy-integration/src/multitenant/mod.rs

@@ -1,3 +1,4 @@
 mod contention;
+mod ore_order;
 mod set_keyset_id;
 mod set_keyset_name;