fix(electrumx): probe bitcoin-knots/bitcoin-core for the daemon host instead of hardcoding knots

The manifest baked bitcoin-knots:8332 into DAEMON_URL. Nodes whose
backend runs under the bitcoin-core name (and any future variant
without a knots DNS alias) left electrumx permanently disconnected —
'connection problem' forever and a block index stuck at 0. The
startup script now picks the first backend name that resolves on
archy-net and falls back to bitcoin-knots.

Catalog regenerated (catalog manifests override disk ones fleet-wide);
this regen also embeds the recently-merged barkd/Ark manifest for the
first time.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

apps/electrumx/manifest.yml

@@ -10,9 +10,16 @@ app:
     network: archy-net
     data_uid: "1000:1000"
     entrypoint: ["sh", "-lc"]
+    # The bitcoin backend container is bitcoin-knots OR bitcoin-core depending
+    # on which version the node runs (multi-version switch) — probe which name
+    # resolves on archy-net instead of hardcoding knots, which left electrumx
+    # permanently disconnected (block index 0) on core nodes.
     custom_args:
       - >-
-        export DAEMON_URL="http://archipelago:$(printenv BITCOIN_RPC_PASS)@bitcoin-knots:8332/";
+        for h in bitcoin-knots bitcoin-core; do
+        if getent hosts "$h" >/dev/null 2>&1; then BTC_HOST="$h"; break; fi;
+        done;
+        export DAEMON_URL="http://archipelago:$(printenv BITCOIN_RPC_PASS)@${BTC_HOST:-bitcoin-knots}:8332/";
         exec electrumx_server
     secret_env:
       - key: BITCOIN_RPC_PASS