v0.5.1 — degraded-honesty across score + share surfaces

Every score surface now distinguishes "feed unreachable" from "nothing live": live/today/match and the share variants (share live/<id>/<date>, MCP get_share_snippet) flag degraded on an outage, show a feed-down notice, stamp static cards "not live", and drop provider attribution — so an outage can never render or paste as an authoritative empty/scheduled card. Also forces the shipped transitive hono to >=4.12.25 (clears four audit advisories).