feat(curator): make skill consolidation opt-in (prune stays default-on) (#47840)

The curator now defaults to prune-only: the deterministic inactivity pass
(mark stale / archive long-unused skills) still runs whenever the curator is
enabled, but the opinionated LLM umbrella-building consolidation fork is OFF
by default.

- agent/curator.py: add DEFAULT_CONSOLIDATE=False + get_consolidate(); gate
  the forked aux-model review in run_curator_review behind it (new consolidate
  param, None=read config). When off, the LLM pass is skipped entirely (no
  aux-model cost); the run is still recorded and reported.
- config.py: add curator.consolidate (default false); v29->v30 migration seeds
  the key for existing installs without clobbering a user-set value.
- hermes_cli/curator.py: 'hermes curator run --consolidate' override; status
  shows consolidate state; prune-only notice on run.
- docs + tests.

tests/agent/test_curator.py

@@ -520,7 +520,7 @@ def test_dry_run_injects_report_only_banner(curator_env, monkeypatch):
                 "tool_calls": [], "error": None}
     monkeypatch.setattr(c, "_run_llm_review", _stub)
 
-    c.run_curator_review(synchronous=True, dry_run=True)
+    c.run_curator_review(synchronous=True, dry_run=True, consolidate=True)
     assert "DRY-RUN" in captured["prompt"]
     assert "DO NOT" in captured["prompt"]
 
@@ -571,7 +571,11 @@ def test_run_review_synchronous_invokes_llm_stub(curator_env, monkeypatch):
     monkeypatch.setattr(c, "_run_llm_review", _stub)
 
     captured = []
-    c.run_curator_review(on_summary=lambda s: captured.append(s), synchronous=True)
+    c.run_curator_review(
+        on_summary=lambda s: captured.append(s),
+        synchronous=True,
+        consolidate=True,
+    )
 
     assert len(calls) == 1
     assert "skill CURATOR" in calls[0] or "CURATOR" in calls[0]
@@ -595,6 +599,69 @@ def test_run_review_skips_llm_when_no_candidates(curator_env, monkeypatch):
     assert any("skipped" in s for s in captured)
 
 
+def test_consolidate_default_off(curator_env):
+    """Consolidation (the LLM umbrella pass) is OFF by default — only the
+    deterministic inactivity prune runs unless the user opts in."""
+    c = curator_env["curator"]
+    assert c.get_consolidate() is False
+
+
+def test_consolidate_enabled_via_config(curator_env, monkeypatch):
+    c = curator_env["curator"]
+    monkeypatch.setattr(c, "_load_config", lambda: {"consolidate": True})
+    assert c.get_consolidate() is True
+
+
+def test_run_review_skips_llm_when_consolidate_off(curator_env, monkeypatch):
+    """With consolidation off (the default), a run does the deterministic
+    prune but never spawns the LLM consolidation fork — even with candidates
+    present. The run is still recorded and a 'consolidation off' summary is
+    surfaced."""
+    c = curator_env["curator"]
+    u = curator_env["usage"]
+    skills_dir = curator_env["home"] / "skills"
+    _write_skill(skills_dir, "a")
+    u.mark_agent_created("a")
+
+    calls = []
+    monkeypatch.setattr(
+        c, "_run_llm_review",
+        lambda prompt: (calls.append(prompt), "never-called")[1],
+    )
+
+    captured = []
+    c.run_curator_review(on_summary=lambda s: captured.append(s), synchronous=True)
+
+    assert calls == []  # LLM consolidation fork not invoked
+    assert any("consolidation off" in s for s in captured)
+    # The run is still recorded (deterministic prune happened).
+    state = c.load_state()
+    assert state["last_run_at"] is not None
+    assert state["run_count"] >= 1
+
+
+def test_run_review_consolidate_override_runs_llm(curator_env, monkeypatch):
+    """Passing consolidate=True overrides the config default (off) and drives
+    the LLM consolidation pass — mirrors `hermes curator run --consolidate`."""
+    c = curator_env["curator"]
+    u = curator_env["usage"]
+    skills_dir = curator_env["home"] / "skills"
+    _write_skill(skills_dir, "a")
+    u.mark_agent_created("a")
+
+    calls = []
+    monkeypatch.setattr(
+        c, "_run_llm_review",
+        lambda prompt: (calls.append(prompt), {
+            "final": "", "summary": "s", "model": "", "provider": "",
+            "tool_calls": [], "error": None,
+        })[1],
+    )
+
+    c.run_curator_review(synchronous=True, consolidate=True)
+    assert len(calls) == 1
+
+
 def test_maybe_run_curator_respects_disabled(curator_env, monkeypatch):
     c = curator_env["curator"]
     monkeypatch.setattr(c, "_load_config", lambda: {"enabled": False})