v0.11.0

Retire the demo-heritage identity so real memory no longer lives under a
throwaway "demo" name (roadmap #16), and fix dense search against remote /
proxied Ollama endpoints.

Changed (BREAKING)

• Default identity is now local / personal (was demo-user /
  yggdrasil-demo). On the first engine start after upgrade, existing memory is
  auto-migrated once — a version-guarded (PRAGMA user_version) SQL relabel
  that only touches the exact legacy demo pair, so a custom identity is never
  moved. A timestamped *.pre-identity-v1.*.bak backup is written first, and the
  resolved identity is pinned explicitly into config.json so no future
  default change can ever strand memory again. FTS is untouched (it indexes
  content, not identity).
• ⚠ ygg sync users: upgrade every synced machine together. The sync key
  format changes with the identity; a lagging demo-keyed peer is auto-adopted to
  the default on import, but mixed versions briefly diverge.

Added

• ygg migrate [--dry-run] — preview or run the identity migration manually
  (backup-first), for when the daemon isn't the one you want to drive it.
• Identity now resolves through a single source of truth (ygg_config.user_id()
  / namespace()); ~15 hardcoded demo-user fallbacks were routed through it, so
  the default can no longer diverge across the codebase. The demo/eval gates pin
  the demo identity explicitly via ygg_config.DEMO_* constants.

Fixed

• Dense search silently degraded to lexical against remote / proxied Ollama.
  Three independent causes, all fixed: the embedder only called the legacy
  /api/embeddings (now falls back to the newer /api/embed that some builds and
  hosted proxies serve instead); it sent no User-Agent, so the Cloudflare proxy
  in front of *.proxy.runpod.net 403'd every request (now identifies as a
  product string, like ygg seed already did); and a dropped request left a
  memory permanently unembedded (now retries transient failures with backoff).

Benchmark

• Grew the retrieval eval corpus from 35 to 232 memories / 110 labelled queries
  (docs/TODO #26) for statistical power — the candidate pool per query roughly
  doubles and the recall CIs tighten. ygg_eval.py now seeds+embeds the corpus
  once (not 6×), shows a progress heartbeat, prints per-query-class recall, and
  warns loudly if a requested embedding model produced no vectors.

Cleanup

• Dedup the copy-pasted YGG_ENGINE_TOKEN or YGG_ENGINE_TOKEN env lookup in four
  gates; drop stale "MVP" wording and engine.s→engine's typos (roadmap #14/#17).