Trino out of the code; commit messages name bands and rules

The rename step in init.sh and the guard in deploy/lib.sh are gone. README's
procedure is now "Removing the old project"; it keeps the old names until it
has run on the server. Migrations stay here (open point 8), and their README
says so. AGENTS.md adds the commit-message rule. Not deployed: live still runs
Trino.

Bands: 4 (Superset), persistence (docs). Rules: 2.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

petrolyst-insights/superset_config.py

@@ -46,7 +46,7 @@ SQLALCHEMY_DATABASE_URI = URL.create(
 ).render_as_string(hide_password=False)
 
 # --- The data: fuel-db ----------------------------------------------------------
-# Superset reads fuel-db directly as the read-only role fuel_ro (no Trino since 29 Oct 2026);
+# Superset reads fuel-db directly as the read-only role fuel_ro;
 # superset-init registers that connection, "Fuel", without a password. Passwords of data
 # connections come from secret files at connect time, so none is kept in Superset's own
 # database. A connection added in the UI gets no password this way.