chore: bump frigate to v1.5.1

[josibake]

Brings, on top of v1.5.0:

• f8b0457 bump to v1.5.1
• ee33934 persist indexed block progress in a separate marker table with startup reorg and orphan-tweak checks
• a3c5a76 use json-rpc batching when fetching transactions for initial mempool indexing
• 36decce cold-sync index logging cleanup (separates fetched from indexed counts)
• cb172a0 use getblock verbosity=3 to inline prevout scripts and skip per-input getrawtransaction
• 15e0bfd fix script-hash subscribe/unsubscribe races, defer headers eligibility with catch-up
• d38423d serialize all client socket writes through a per-handler write lock
• fdf9ac8 release electrum transport read lock during socket reads to avoid client request starvation
• 8fa3f2c document backend per-IP limits and notification ordering
• 8bfde6d include version in startup message

Drongo submodule pointer is unchanged from v1.5.0.