Initial commit of Descrybe v2 without local scratch artifacts.

Drop one-shot tmp/axe scripts and agent i18n scratch so the Gitea tree is deployable.

apps/api/sql/schema/039_worker_heartbeats.sql

@@ -0,0 +1,11 @@
+-- +goose Up
+-- Worker liveness signal for /readyz (API probes fail when the poller is dead).
+
+CREATE TABLE IF NOT EXISTS worker_heartbeats (
+  worker_id TEXT PRIMARY KEY,
+  last_seen_at TIMESTAMPTZ NOT NULL DEFAULT now(),
+  updated_at TIMESTAMPTZ NOT NULL DEFAULT now()
+);
+
+-- +goose Down
+DROP TABLE IF EXISTS worker_heartbeats;