feat: Phase 9 — Tor-by-default for Bitcoin and Lightning

- Bitcoin Knots: added -proxy=127.0.0.1:9050 for P2P connections through Tor
- LND: enabled tor.active=true, tor.socks, tor.streamisolation in lnd.conf
- Tor setup handled by existing archipelago-setup-tor.service at first boot
- .onion display and Tor toggle already present in Settings UI

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

scripts/first-boot-containers.sh

@@ -139,6 +139,7 @@ if ! $DOCKER ps --format '{{.Names}}' 2>/dev/null | grep -qE 'bitcoin-knots|arch
     -server=1 $BTC_EXTRA_ARGS \
     -rpcallowip=127.0.0.1/32 -rpcallowip=10.88.0.0/16 -rpcbind=0.0.0.0:8332 \
     -rpcuser=$BITCOIN_RPC_USER -rpcpassword=$BITCOIN_RPC_PASS \
+    -proxy=127.0.0.1:9050 -listen=1 -bind=0.0.0.0:8333 \
     -dbcache=$BTC_DBCACHE 2>>"$LOG"; then
     log "Bitcoin Knots started"
   else
@@ -291,7 +292,9 @@ rpclisten=0.0.0.0:10009
 restlisten=0.0.0.0:8080
 debuglevel=info
 noseedbackup=true
-tor.active=false
+tor.active=true
+tor.socks=127.0.0.1:9050
+tor.streamisolation=true
 
 [Bitcoin]
 bitcoin.mainnet=true