Grain 0.8.0-rc4

Fourth release candidate for 0.8.0. This pass focuses on a reworked relay dashboard, more reliable cross-relay event resolution in the reference client, and several nostrdb correctness fixes.

Relay dashboard

• Vitals panel beside the live feed - this relay's own event count, active connections, uptime, storage used vs the nostrdb map ceiling, Go heap vs the configured limit, and writer health.
• Top-kinds donut with a Count / Size toggle (rank slices by event count or stored bytes), an instant hover tooltip, and an aligned legend.
• Whitelist / blacklist / policy / purge sections reorganized under Overview Access lists Policy & Limits Retention tabs (same functionality, less scroll).
• Sticky header - the nav bar pins to the top on scroll, app-wide.
• New public endpoint GET /api/v1/relay/stats backing the panel (storage, total events, per-kind count + bytes, heap, write errors).

Reference client

• Outbox-aware event resolution - opening an event now escalates from the local relay to the author's outbox relays, embedded relay hints, and NIP-50 search, so cross-relay events actually resolve instead of coming back empty.
• Live feed reliability - the feed tears down cleanly across navigations (fixes breakage on certain nav paths) and shows the newest events on spin-up.
• "I'm new here" callout surfaced in the login modal.

Database (nostrdb)

• NIP-01 prefix matching for ids and authors (#72) - 1-64 hex-char prefixes matched in-memory and via index range-scan; ends the 00..ff author-probe log spam.
• Configurable NIP-50 fulltext kinds (#71) - new database.fulltext_kinds; defaults to kinds 0, 1, 30023; an explicit empty list disables the text index.
• nostrdb fork sync: newest-first query merge, complete delete, and an ingester-quit race fix (re-ingested repost inner notes no longer strand on shutdown).

Signer

• nostr-mill bumped to 1.8.2 (adds import-key restore).

Docs

• Dashboard-rework and event-rendering design specs (the latter filed as a Beyond-1.0 plan).

Full changelog: https://github.com/0ceanSlim/grain/compare/v0.8.0-rc3...v0.8.0-rc4