fix(phoenixd): dot-free datadir + data_uid; docs: iframe rules

phoenixd: the orchestrator treats bind paths containing a dot as file
mounts and never creates their source dir, so the image's default
/phoenix/.phoenix target crash-looped the unit (statfs: no such file).
Datadir moved to /data via PHOENIX_DATADIR; data_uid 1000:1000 matches the
image's phoenix user — without it phoenixd dies on phoenix.conf
'Permission denied'. Both verified end-to-end on archi-dev-box: orch
install OK, seed.dat + db on the host, authenticated /getinfo answers.

alby-hub: launch flips to embedded — pairs with the gate change that
neutralizes upstream frame blocking.

Dev guide: iframe embedding rules (who blocks framing and why the gate
may strip it; when open_in_new_tab is legitimate; test in the embedded
session, never a tab).

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

apps/alby-hub/manifest.yml

@@ -64,7 +64,10 @@ app:
     repo: https://github.com/getAlby/hub
     tier: optional
     launch:
-      open_in_new_tab: true
+      # Embedded: the gate neutralizes Alby Hub's X-Frame-Options: DENY on
+      # proxied responses. Nodes older than the gate fix show a blocked
+      # frame — flip to true only if targeting such nodes.
+      open_in_new_tab: false
     features:
       - Self-custodial Lightning node (LDK) with a friendly wallet UI
       - Connect wallets and apps via Nostr Wallet Connect (NWC)