Featurizer 0.9.1

Phase 5 of the text/graph plan: trajectory, sequence extensions, and the
Path-2 move where text induces the graph. Everything here is a φ-bridge or
edge builder — zero engine change.

Added

• EmbeddingTrajectoryBridge (featurizer/bridge/trajectory.py, numpy
  only): per-event novelty (1 − max cosine to the entity's own
  strictly-prior embeddings — "out of character?"), drift (distance to the
  prior-history centroid), and volatility (step distance to the previous
  event). First events are NULL (no history ≠ maximal novelty); accepts
  Python sequences, PostgreSQL arrays, or pgvector text — a materialized
  SentenceEmbeddingBridge table reads back directly.
• Sequence extensions (featurizer/bridge/changepoint.py, numpy only,
  snapshot-aware per ADR-0014): ChangePointBridge — strongest mean shift in
  an entity's pre-t₀ measure series (binary-segmentation score + 0–1
  position); PeriodicityBridge — FFT-peak strength and dominant period of
  the binned event-count series (7 with daily bins and a weekly rhythm).
• Text-induced edges (featurizer/bridge/edges.py, Path 2): a small
  EdgeBridge base whose materialize_edges writes an (src, dst, ts)
  table — exactly what the graph bridges and the native
  graph_relationships stage consume. NearDuplicateEdgeBridge (MinHash/LSH
  via datasketch; an edge between the entities of near-duplicate documents,
  knowable at the later document's timestamp; self-copies excluded) and
  CoMentionEdgeBridge (names mentioned together per document; naive
  built-in extractor, extract= pluggable). The two-stage
  text→edges→centrality→spine wiring is integration-tested end to end and
  documented in the bridge cookbook.
• Shared bridge plumbing (load_rows, fit_slice, create_table_sql,
  value_sql_type) promoted to public module functions in
  featurizer/bridge/base.py; word_tokens public in .nlp. Behaviour
  unchanged.
• Deps: datasketch joins the [bridge] extra and the dev group (the
  near-duplicate tests execute under plain uv sync).
• Tests: 24 new DB-free (planted outlier / step / weekly-rhythm / copy-paste
  signals all recovered; per-entity and strictly-prior history isolation) +
  the live-PG two-stage pipeline test.