feat(synthesis): Lead/Provenance model + grounded leads + conjecture generator

- codex/synthesis.py: Lead/Provenance dataclasses, find_connections/gaps/improvements,
  propose_conjectures (status=unverified, quarantined in leads/conjectures/),
  write_leads (grounded→leads/grounded/, conjectures→leads/conjectures/ HARD invariant)
- codex/cli.py: synthesis leads/conjectures/report command group
- codex/config.py: F-13 settings (leads_dir, synthesis_llm_*, synthesis_top_k,
  synthesis_min_grounded_ratio, synthesis_gap_min_coverage)
- tests/synthesis/: 42 tests covering model, grounding, conjecture invariant, quarantine, CLI
- spike/: F-13 spike script + output (live run attempted)

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

spike/F13_synthesis_spike.py

@@ -0,0 +1,141 @@
+"""F-13 synthesis spike — quick live-infra evaluation (WEGWERF-CODE).
+
+NOT a unit test. Not maintained. Run by hand against live infrastructure:
+
+  DB:    postgresql://researcher:change_me@localhost:5432/papers (podman, Mac)
+  LLM:   http://192.168.178.103:11434 (Jetson, qwen2.5:7b)
+
+Goal: emit 3-5 grounded leads (connection + gap) and a couple of
+conjectures, then eyeball:
+
+  * Grounded-Lead-Präzision: anteil echter (nicht scheinbarer) Lücken /
+    Verbindungen. Ziel ≥ 60 %.
+  * Zero-Fact-Leak: jede Konjektur trägt status="unverified" und landet
+    in leads/conjectures/, NIE in wiki/.
+
+Result is dumped to ``spike/spike_output.json`` and stdout.
+"""
+
+from __future__ import annotations
+
+import json
+import os
+import sys
+from pathlib import Path
+
+# Wire up the live infra without polluting ~/.env
+os.environ.setdefault("DATABASE_URL", "postgresql://researcher:change_me@localhost:5432/papers")
+os.environ.setdefault("OLLAMA_BASE_URL", "http://192.168.178.103:11434")
+os.environ.setdefault("SYNTHESIS_LLM_MODEL", "qwen2.5:7b")
+os.environ.setdefault("SYNTHESIS_TOP_K", "12")
+
+ROOT = Path(__file__).resolve().parent.parent
+sys.path.insert(0, str(ROOT))
+
+
+def _probe_db() -> bool:
+    try:
+        import psycopg
+
+        with psycopg.connect(os.environ["DATABASE_URL"]) as conn:
+            n = conn.execute("SELECT count(*) FROM papers").fetchone()
+            print(f"[db ok] papers={n[0] if n else '?'}")
+            return True
+    except Exception as exc:
+        print(f"[db FAIL] {exc}")
+        return False
+
+
+def _probe_llm() -> bool:
+    import httpx
+
+    try:
+        r = httpx.get(os.environ["OLLAMA_BASE_URL"] + "/api/tags", timeout=3.0)
+        r.raise_for_status()
+        print(f"[llm ok] models={len(r.json().get('models', []))}")
+        return True
+    except Exception as exc:
+        print(f"[llm FAIL] {exc}")
+        return False
+
+
+def run() -> dict[str, object]:
+    if not _probe_db():
+        return {"error": "db unreachable", "live": False}
+    if not _probe_llm():
+        return {"error": "llm unreachable", "live": False}
+
+    from codex.config import get_settings  # noqa: E402  (after env wiring)
+    from codex.synthesis import (
+        default_llm_client,
+        find_connections,
+        find_gaps,
+        propose_conjectures,
+        write_leads,
+    )
+
+    # Reset settings cache so DB/LLM env wiring above is picked up
+    get_settings.cache_clear()
+    settings = get_settings()
+    print(f"[settings] top_k={settings.synthesis_top_k} model={settings.synthesis_llm_model}")
+
+    llm = default_llm_client()
+
+    print("\n--- find_connections ---")
+    connections = find_connections(top_k=settings.synthesis_top_k, llm=llm)
+    print(f"  {len(connections)} connection leads")
+    for c in connections:
+        print(f"  - {c.id}: {c.title}  (conf={c.confidence:.2f})")
+
+    print("\n--- find_gaps (no lib_path) ---")
+    gaps = find_gaps(llm=llm)
+    print(f"  {len(gaps)} gap leads")
+    for g in gaps:
+        print(f"  - {g.id}: {g.title}  (conf={g.confidence:.2f})")
+
+    print("\n--- propose_conjectures ---")
+    conjectures = propose_conjectures(top_k=settings.synthesis_top_k, llm=llm)
+    print(f"  {len(conjectures)} conjectures")
+    for cj in conjectures:
+        print(f"  - {cj.id}: {cj.title}")
+        print(f"      status={cj.status}  validation={cj.suggested_validation[:80]}")
+
+    # Write into a sandbox dir
+    sandbox = ROOT / "spike" / "spike_output"
+    sandbox.mkdir(parents=True, exist_ok=True)
+    write_leads(connections + gaps + conjectures, str(sandbox))
+
+    # ZERO-FACT-LEAK guard: no conjectures in grounded/, every conjecture has validation
+    leak = False
+    for cj in conjectures:
+        if cj.kind != "conjecture":
+            leak = True
+            print(f"[LEAK] {cj.id} kind={cj.kind}")
+        if cj.status != "unverified":
+            leak = True
+            print(f"[LEAK] {cj.id} status={cj.status} (expected unverified)")
+        if not cj.suggested_validation:
+            leak = True
+            print(f"[LEAK] {cj.id} missing suggested_validation")
+        if not cj.provenance:
+            leak = True
+            print(f"[LEAK] {cj.id} missing provenance")
+
+    summary = {
+        "live": True,
+        "leak": leak,
+        "counts": {
+            "connection": len(connections),
+            "gap": len(gaps),
+            "conjecture": len(conjectures),
+        },
+        "leads_dir": str(sandbox),
+    }
+    (ROOT / "spike" / "spike_output.json").write_text(json.dumps(summary, indent=2))
+    print("\n=== SUMMARY ===")
+    print(json.dumps(summary, indent=2))
+    return summary
+
+
+if __name__ == "__main__":
+    run()

spike/spike_output.json

@@ -0,0 +1,10 @@
+{
+  "live": true,
+  "leak": false,
+  "counts": {
+    "connection": 0,
+    "gap": 0,
+    "conjecture": 0
+  },
+  "leads_dir": "/Users/tarikmoussa/Desktop/codex-py/spike/spike_output"
+}

spike/spike_output/INDEX.md

@@ -0,0 +1,11 @@
+# Lead Index
+
+_Last updated 2026-06-14 06:35 UTC by `codex synthesis`_
+
+## Grounded leads (connection / gap / improvement)
+
+_None._
+
+## Conjectures (UNVERIFIED — quarantined here, never in wiki/)
+
+_None._