- Replace stale "service" role option with correct set:
admin, user, guest, viewer, editor, commenter (matches model.go)
- Add Form/JSON tab toggle to policy create form
- JSON tab accepts raw RuleBody JSON with description/priority
- Handler detects rule_json field and parses/validates it
directly, falling back to field-by-field form mode otherwise
* web/templates/pgcreds.html: New Credentials card is now always
rendered; Add Credentials toggle button reveals the create form
(hidden by default). Shows a message when all system accounts
already have credentials. Previously the card was hidden when
UncredentialedAccounts was empty.
* internal/ui/ui.go: added ActorName string field to PageData;
added actorName(r) helper resolving username from JWT claims
via DB lookup, returns empty string if unauthenticated.
* internal/ui/handlers_*.go: all full-page PageData constructors
now pass ActorName: u.actorName(r).
* web/templates/base.html: nav bar renders actor username as a
muted label before the Logout button when logged in.
* web/static/style.css: added .nav-actor rule (muted grey, 0.85rem).
