Phase 14: dreaming as an opt-in, budgeted, non-acting idle mode

- dreaming.Service: deterministic memory replay sample keyed by dream id,
  vocabulary-based association of unlinked memory pairs (similar_to edges +
  dream_association events), speculative hypotheses as hypothesis-kind beliefs
  with two weak memory citations (starts ~0.30, asserted <= 0.35)
- Run marks the context forbidden for capabilities before anything else;
  test proves Invoke refuses inside a dream
- per-mind settings: enabled (default off), hours window (wraps midnight),
  interval, model-call / memory / hypothesis caps; global pause switch
- optional model wording via new `dream` prompt (role hypothesise)
- promotion adds operator evidence, rejection retracts the belief; both
  audited and recorded as operator actions
- migration 0014, API, Dreams tab and page, noemactl dreams, docs/dreaming.md

docs/dreaming.md

@@ -0,0 +1,42 @@
+# Dreaming
+
+Dreaming is an optional idle mode (spec §19). It is **off by default**. When
+enabled, and only inside the allowed hours, a mind periodically:
+
+1. **Replays** a deterministic sample of recent episodic and semantic memories
+   (the sample is a function of the dream id, so a dream can be replayed).
+2. **Associates** pairs that share vocabulary (Jaccard within a band, excluding
+   near-duplicates and same-episode pairs) but were never linked. Each new link
+   is a `similar_to` relationship with low confidence and a `dream_association`
+   event citing both memories.
+3. **Proposes** speculative hypotheses for the strongest pairs. Wording is
+   deterministic unless a budgeted model call (role `hypothesise`, prompt
+   `dream`) offers a better one. The model never decides truth.
+
+## Guarantees
+
+- **Dreams cannot act.** `Run` marks its context forbidden for the capability
+  layer before doing anything; any `Invoke` reached from a dream returns
+  `ErrForbiddenContext`. There is no code path from dreaming to an executor.
+- **Low confidence by construction.** Every hypothesis is a belief with
+  epistemic kind `hypothesis` (prior 0.25) and two memory citations at weight
+  0.1, giving roughly 0.30. The test suite asserts ≤ 0.35. Confidence can only
+  rise through ordinary evidence.
+- **Nothing is rewritten.** Sampled memories are untouched. Rejecting a
+  hypothesis retracts its belief; promoting adds an operator endorsement as
+  evidence, so the arithmetic stays inspectable on the belief page.
+- **Budgeted.** Per-mind model-call, memory and hypothesis caps; a global pause
+  switch; scheduled dreams need enabled + hours window + interval elapsed.
+
+## Operating
+
+- UI: mind → **Dreams**. Review proposed hypotheses (promote / reject), see
+  dreams with counts, change settings (administrator).
+- API: `GET /api/v1/minds/{mind}/dreams`, `POST …/dreams/run`,
+  `POST …/dreams/settings`, `POST …/dreams/hypotheses/{id}/promote|reject`,
+  `POST /api/v1/dreams/pause`.
+- CLI: `noemactl dreams <mind> list|run|promote <id> [note]|reject <id> [reason]`.
+
+Settings (`CognitiveConfig`): `dreaming_enabled`, `dream_hours` (`HH-HH` local,
+may wrap midnight, blank = any), `dream_interval`, `dream_llm_calls`,
+`dream_max_memories`, `dream_max_hypotheses`.