Apply the image decision tree to missing hall portraits

A hall visual that stays on the general branch uses the Efficient model
from the 2026-10-08 intelligence-radar tree. render-hall writes only
portraits whose files are still absent.

Assistant: grok
Assistant-Session: 01a11ab6-1534-7d63-8606-662b92a80ed6

tests/test_image_selection.py

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+"""Decision tree and hall portrait planning."""
+
+import json
+from pathlib import Path
+
+from llm_connect.cli import main
+from llm_connect.hall_portraits import plan_missing_portraits, reveal_portrait
+from llm_connect.image_selection import classify_image_branch, selection_for_prompt
+
+HALL_PROMPT = (
+    "Constellation dialect. Square, dark indigo. A gold-wire helix. "
+    "Fine technical-illustration linework, no logos, no readable text."
+)
+
+
+def test_hall_house_prompt_is_general_efficient() -> None:
+    selection = selection_for_prompt(HALL_PROMPT)
+    assert classify_image_branch(HALL_PROMPT) == "general"
+    assert selection.tier == "efficient"
+    assert selection.model == "google/gemini-nano-banana-2.1"
+    assert selection.quote_usd == 0.04
+    assert selection.max_cost_usd == 0.08
+
+
+def test_negated_text_does_not_become_text_heavy() -> None:
+    assert classify_image_branch("no logos, no readable text, pale gold") == "general"
+
+
+def test_abstract_marks_stay_on_the_general_branch() -> None:
+    prompt = (
+        "a ledger glows with the words rendered as abstract marks, not readable text. "
+        "no logos, no lettering"
+    )
+    assert classify_image_branch(prompt) == "general"
+
+
+def test_requested_words_take_the_text_branch() -> None:
+    selection = selection_for_prompt("A poster whose headline is the words HELIX")
+    assert selection.branch == "text_heavy"
+    assert selection.model == "openai/gpt-image-2.5-sunburst"
+
+
+def test_vector_and_self_host_follow_the_tree() -> None:
+    assert selection_for_prompt("Export as a vector svg icon").model.startswith("recraft/")
+    try:
+        selection_for_prompt("self-host the open weights on our own hardware")
+    except Exception as exc:
+        assert "OpenRouter" in str(exc)
+    else:
+        raise AssertionError("self-host branch should refuse")
+
+
+def _entry(visual: str, comment: str | None, entry_id: str = "hall-worker-ada-1") -> str:
+    commented = f"<!-- ![{comment}](../visuals/ada.jpg) -->\n" if comment else ""
+    return f"""---
+id: {entry_id}
+status: draft
+---
+
+# Ada — a seat
+
+## Visual prompt
+
+> {visual}
+
+{commented}
+## Handoff
+
+Next.
+"""
+
+
+def test_plan_skips_a_portrait_that_is_already_on_disk(tmp_path: Path) -> None:
+    entries = tmp_path / "entries"
+    visuals = tmp_path / "visuals"
+    entries.mkdir()
+    visuals.mkdir()
+    (entries / "one.md").write_text(_entry(HALL_PROMPT, "Ada"), encoding="utf-8")
+    (entries / "two.md").write_text(_entry(HALL_PROMPT, None, "hall-worker-bea-2"), encoding="utf-8")
+    (visuals / "bea-file.jpg").write_bytes(b"x")
+    # two.md has no comment, so its derived file is the id. Put that file on disk.
+    (visuals / "hall-worker-bea-2.jpg").write_bytes(b"x")
+
+    jobs = plan_missing_portraits(tmp_path)
+    assert [job.entry_id for job in jobs] == ["hall-worker-ada-1"]
+    assert jobs[0].output_path == visuals / "ada.jpg"
+    assert jobs[0].relative_path == "../visuals/ada.jpg"
+    assert jobs[0].alt == "Ada"
+    assert "no readable text" in jobs[0].prompt
+
+
+def test_reveal_portrait_uncomments_the_intended_line() -> None:
+    text = _entry(HALL_PROMPT, "Ada")
+    updated = reveal_portrait(text, "../visuals/ada.jpg", "Ada")
+    assert "<!--" not in updated
+    assert "![Ada](../visuals/ada.jpg)" in updated
+    assert "status: draft" in updated
+
+
+def test_plan_reads_a_prompt_that_is_not_a_blockquote(tmp_path: Path) -> None:
+    entries = tmp_path / "entries"
+    visuals = tmp_path / "visuals"
+    entries.mkdir()
+    visuals.mkdir()
+    body = """---
+id: hall-worker-cy-3
+status: draft
+---
+
+# Cy — a seat
+
+## Visual prompt
+
+**Dialect:** Constellation. Square, no logos, no readable text.
+
+A gold-wire orrery suspended in dark indigo.
+
+## Handoff
+
+Next.
+"""
+    (entries / "three.md").write_text(body, encoding="utf-8")
+    jobs = plan_missing_portraits(tmp_path)
+    assert len(jobs) == 1
+    assert "orrery" in jobs[0].prompt
+    assert jobs[0].output_path.name == "hall-worker-cy-3.jpg"
+
+
+def test_cli_plan_is_dry_and_names_the_efficient_model(tmp_path: Path, capsys) -> None:
+    entries = tmp_path / "entries"
+    visuals = tmp_path / "visuals"
+    entries.mkdir()
+    visuals.mkdir()
+    (entries / "one.md").write_text(_entry(HALL_PROMPT, "Ada"), encoding="utf-8")
+    code = main(["image", "plan", "--hall", str(tmp_path), "--json"])
+    assert code == 0
+    payload = json.loads(capsys.readouterr().out)
+    assert payload["count"] == 1
+    assert payload["jobs"][0]["model"] == "google/gemini-nano-banana-2.1"
+    assert payload["max_batch_cost_usd"] == 0.08
+    assert not (visuals / "ada.jpg").exists()