feat(prompting): Phase B step 2 — wire the sharded poker prompt into the pipeline

build_messages now shards poker_cash: injects poker_prompts.BASE + exactly ONE
fragment chosen by classify(user_msg, roster_handles), replacing the ~100-line
_CASH_CARD monolith. Roster handles are fetched fail-safe from the live session so
the READ-vs-HAND split is reliable. CASH.card set to "" (monolith kept only as the
distillation source, superseded). Other modes' single-card path unchanged.

Verified end-to-end: TAG-limp→READ, his-hand→HAND, table-broke→TABLE, tilt→MENTAL,
bare-stack→LOG, all with BASE always present. 5 injection/pipeline tests. Full
suite 196 green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/test_perceive.py

@@ -74,4 +74,32 @@ def test_mode_menu_note_suppressed_in_poker(mind):
     build = " ".join(m["content"] for m in mind.build_messages("s1", "let's refactor", mode=modes.get("build"))
                      if m["role"] == "system")
     assert "Your modes:" not in poker                # no "offer to switch" note at the table
-    assert "Your modes:" in build                    # still present in a non-poker mode
+    assert "Your modes:" in build                    # still present in a non-poker mode
+
+
+# --- Phase B: sharded poker prompt (BASE + one fragment, no monolith) ---
+
+def _poker_blob(mind, msg):
+    from lyra import modes
+    return " ".join(m["content"] for m in mind.build_messages("s1", msg, mode=modes.CASH)
+                    if m["role"] == "system")
+
+
+def test_poker_injects_base_plus_the_matching_fragment(mind):
+    blob = _poker_blob(mind, "I flopped a set with 99 on 9h4c2d and bet the turn")
+    assert "LOG FIRST" in blob                       # BASE is always on in poker
+    assert "MESSAGE TYPE: HAND" in blob              # the fragment for THIS message
+    assert "MESSAGE TYPE: STATUS" not in blob        # and not the others
+    assert "MESSAGE TYPE: READ" not in blob
+
+
+def test_poker_fragment_changes_with_message_type(mind):
+    status = _poker_blob(mind, "it's 11:50pm, waiting for a seat")
+    assert "MESSAGE TYPE: STATUS" in status and "MESSAGE TYPE: HAND" not in status
+
+
+def test_poker_monolith_no_longer_injected(mind):
+    from lyra import modes
+    blob = _poker_blob(mind, "stack 350")
+    assert "You move between two registers" not in blob   # the old _CASH_CARD opener is gone
+    assert modes.CASH.card == ""                           # card sharded out