feat(guards): memory/context budget checks + multi-round T>=2 orchestrator tests

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tests/test_orchestrator_t2.py

@@ -0,0 +1,54 @@
+from unittest.mock import MagicMock
+
+from markovian_rsa_mlx.batching import GenerationResult
+from markovian_rsa_mlx.config import RSAConfig
+from markovian_rsa_mlx.orchestrator import MarkovianRSAOrchestrator
+
+
+def _tok(eos_id=999):
+    t = MagicMock()
+    t.encode.side_effect = lambda s: [ord(c) for c in s][:32] or [1]
+    t.decode.side_effect = lambda ids: "".join(chr(min(i, 122)) for i in ids if 32 <= i <= 122)
+    t.eos_token_id = eos_id
+    t.all_special_ids = [eos_id]
+    t.apply_chat_template.side_effect = lambda messages, **kw: \
+        " ".join(m["content"] for m in messages).encode()
+    return t
+
+
+def _gen(model, tokenizer, prompt_token_ids, *, max_tokens, seed, temperature, top_p, top_k):
+    text = f"r-trace-{seed}"
+    ids = [ord(c) for c in text]
+    return GenerationResult(token_ids=ids, text=text, generated_tokens=len(ids),
+                            finish_reason="eos", elapsed_s=0.01)
+
+
+def test_t2_two_rounds_aggregation_sees_K_tails(tmp_path):
+    cfg = RSAConfig(rounds=2, parallel=2, aggregation_subsample=2,
+                    chunk_tokens=64, tail_tokens=4, serial=True, seed=7)
+    orch = MarkovianRSAOrchestrator(
+        model=MagicMock(), tokenizer=_tok(),
+        model_id="m", quantization="bf16",
+        single_generate=_gen, batch_generate=None,
+    )
+    audit = tmp_path / "audit.jsonl"
+    text, result = orch.solve("Solve this", config=cfg, return_audit=True, audit_path=audit)
+    assert len(result.rounds) == 2
+    assert len(result.rounds[1].traces) == 2
+    # round 1 traces have parent links
+    assert all(t.parent_trace_ids for t in result.rounds[1].traces)
+
+
+def test_deterministic_seeds_are_stable(tmp_path):
+    cfg = RSAConfig(rounds=2, parallel=2, aggregation_subsample=2,
+                    chunk_tokens=8, tail_tokens=2, serial=True, seed=42)
+    orch = MarkovianRSAOrchestrator(
+        model=MagicMock(), tokenizer=_tok(),
+        model_id="m", quantization="bf16",
+        single_generate=_gen, batch_generate=None,
+    )
+    _, r1 = orch.solve("Q", config=cfg, return_audit=True, audit_path=tmp_path / "a.jsonl")
+    _, r2 = orch.solve("Q", config=cfg, return_audit=True, audit_path=tmp_path / "b.jsonl")
+    seeds_1 = [t.seed for r in r1.rounds for t in r.traces]
+    seeds_2 = [t.seed for r in r2.rounds for t in r.traces]
+    assert seeds_1 == seeds_2