content(sim): rotating clip pools + progressive tracked labels & emotions

Content-pipeline Increment 2, part 1 (the experience). Implements design §11
(docs/superpowers/specs/2026-06-24-content-pipeline-design.md):

- Rotating pool (§11.1): each ring scale references a POOL of vetted clips
  (docs/content-candidate-pool.md); the player picks a random member on landing.
  player.ring.Scale gains `pool` + pure `pick_clip_id(scale, r)` (injected
  randomness); the pick happens at the API boundary (random.random()), a delta=0
  advance is the initial/re-roll pick. clips.py parses/exposes the pool; the
  client lands on move.target_clip_id. Back-compat: a scale with only clip_id is
  a pool of one.
- Rename ring scale forest -> coast (new land<->sea scale, orbit..reef); ring
  order cosmos -> orbit -> coast -> reef -> abyss -> wrap. Cleanup: dropped the
  leftover local media (cosmos_traverse, orbit_westcoast, old forest/reef, the
  Increment-1 orbit/abyss single bases); new coast-edge transition placeholders.
- Time-windowed tracked labels (§11.2): annotations gain appear/disappear
  (loop-normalized, wraps across the seam); a label shows only while on screen
  and its box tracks the subject. abyss + reef pools authored as test material.
- Progressive LEFT detail tiers (§11.3): per-object `salience` (first shows at
  Left 5-salience) + tiered strings (general -> specific -> scientific -> +fact)
  escalating with the Left knob; replaces flat min_level gating. Strings may be a
  tier list or a static string (back-compat). No engine change (client reads
  overlay.level).
- Progressive RIGHT emotion tiers (§11.4): affect vocabulary escalates basic ->
  compound with the Right knob (dream.strength); appearance still gated by
  min(left,right). No engine change.

New simulator/build_pool_manifest.py holds the hand-authored content and emits
the 19-clip pool manifest (the reproducible baseline). setup_scales_media.py
marked superseded. 251 passed / 4 skipped (+ ring pool + API pool/window tests).
By-eye visual review deferred to the operator (no Chrome on this box).

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

tests/test_player_ring.py

@@ -8,6 +8,7 @@ from player.ring import (
     Transition,
     TransitionStep,
     advance_ring,
+    pick_clip_id,
     scale_at,
 )
 
@@ -206,3 +207,36 @@ def test_fast_spin_noop_on_degenerate_ring():
     move = advance_ring(r, from_index=0, delta=9, fast_spin_threshold=3)
     assert move.fast is False
     assert move.steps == ()
+
+
+# --- rotating clip pool (content-pipeline design §11.1) ---
+
+
+def test_scale_without_pool_is_a_pool_of_one():
+    s = Scale(id="cosmos", clip_id="cosmos")
+    assert s.members == ("cosmos",)
+    # any r maps to the single member
+    assert pick_clip_id(s, 0.0) == "cosmos"
+    assert pick_clip_id(s, 0.99) == "cosmos"
+
+
+def test_scale_with_pool_exposes_all_members():
+    s = Scale(id="coast", clip_id="coast_a", pool=("coast_a", "coast_b", "coast_c"))
+    assert s.members == ("coast_a", "coast_b", "coast_c")
+
+
+def test_pick_clip_id_selects_member_by_injected_r():
+    s = Scale(id="coast", clip_id="a", pool=("a", "b", "c", "d"))
+    # r in [0,1) partitions the pool into len equal buckets
+    assert pick_clip_id(s, 0.0) == "a"
+    assert pick_clip_id(s, 0.24) == "a"
+    assert pick_clip_id(s, 0.25) == "b"
+    assert pick_clip_id(s, 0.5) == "c"
+    assert pick_clip_id(s, 0.75) == "d"
+
+
+def test_pick_clip_id_clamps_out_of_range_r():
+    s = Scale(id="coast", clip_id="a", pool=("a", "b", "c"))
+    assert pick_clip_id(s, -5.0) == "a"      # below 0 clamps to first
+    assert pick_clip_id(s, 1.0) == "c"        # 1.0 must not index past the end
+    assert pick_clip_id(s, 999.0) == "c"

tests/test_simulator_api.py

@@ -189,3 +189,64 @@ def test_ring_404_when_no_ring_in_manifest(client):
 def test_ring_advance_rejects_bad_delta(ring_client):
     resp = ring_client.post("/api/ring/advance", json={"from_index": 0, "delta": "x"})
     assert resp.status_code == 422
+
+
+# --- rotating clip pool (content-pipeline §11.1) ---
+
+
+@pytest.fixture
+def pool_client(tmp_path):
+    p = tmp_path / "manifest.json"
+    members = ["coast_a", "coast_b", "coast_c", "coast_d"]
+    clips = [{"id": "cosmos", "title": "Cosmos", "base_file": "cosmos/base.mp4",
+              "license": "PD", "source": "NASA", "right_variants": {},
+              "annotations": [], "affect": [], "strings": {}}]
+    clips += [{"id": m, "title": m, "base_file": f"{m}/base.mp4", "license": "PD",
+               "source": "NPS", "right_variants": {}, "annotations": [], "affect": [],
+               "strings": {}} for m in members]
+    p.write_text(json.dumps({
+        "clips": clips,
+        "ring": {
+            "scales": [
+                {"id": "cosmos", "clip_id": "cosmos"},
+                {"id": "coast", "clip_id": members[0], "pool": members},
+            ],
+            "transitions": [
+                {"file": "transitions/cosmos-coast.mp4"},
+                {"file": "transitions/coast-cosmos.mp4"},
+            ],
+        },
+    }))
+    return TestClient(create_app(manifest_path=p)), members
+
+
+def test_ring_exposes_each_scales_pool(pool_client):
+    client, members = pool_client
+    data = client.get("/api/ring").json()
+    coast = next(s for s in data["scales"] if s["id"] == "coast")
+    assert [m["clip_id"] for m in coast["pool"]] == members
+    # a single-clip scale still reports a pool of one
+    cosmos = next(s for s in data["scales"] if s["id"] == "cosmos")
+    assert [m["clip_id"] for m in cosmos["pool"]] == ["cosmos"]
+
+
+def test_advance_into_a_pool_lands_on_a_member(pool_client):
+    client, members = pool_client
+    # landing on the coast scale (index 1) must pick one of its pool members
+    seen = set()
+    for _ in range(40):
+        data = client.post("/api/ring/advance", json={"from_index": 0, "delta": 1}).json()
+        assert data["to_index"] == 1
+        assert data["target_clip_id"] in members
+        seen.add(data["target_clip_id"])
+    # over many landings the random pick should cover more than one member
+    assert len(seen) > 1
+
+
+def test_delta_zero_is_an_initial_pool_pick(pool_client):
+    client, members = pool_client
+    # a no-op (delta 0) advance on the pool scale is the initial / re-roll pick
+    data = client.post("/api/ring/advance", json={"from_index": 1, "delta": 0}).json()
+    assert data["to_index"] == 1
+    assert data["steps"] == []
+    assert data["target_clip_id"] in members