Two related polish items:
1. Optional custom block explorer. New union under Advanced config
("Block Explorer") defaulting to "mempool.space". Picking
"Custom URL" reveals a single text field where the user can
point Kamado at their own mempool instance — useful for users
running mempool as a sibling StartOS service or on the same LAN.
The entrypoint reads .advanced.mempool-explorer.{type,url} and
exports MEMPOOL_BASE_URL when type=custom; otherwise leaves it
empty and the UI keeps its mempool.space defaults.
2. stunnel debug level 4 (warning) was hiding successful TLS
handshakes — only failures showed up in the service logs, which
made it hard to confirm "yes, my miner did connect over TLS"
without going looking at netstat. Bump to level 5 (notice) so
each successful handshake produces an "accepted connection from
<ip>" / "connected from <ip>" line. Errors stay visible at level
3, so the only thing this changes is making the happy path
observable.
satoshi
4be06d347c