fix: enable env vars in setup steps (and deprecate admin subcommand) (#3871)

* fix: enable env vars in setup steps (and deprecate admin subcommand)

* fix tests and error text

cmd/setup/02.go

@@ -0,0 +1,36 @@
+package setup
+
+import (
+	"context"
+	"database/sql"
+)
+
+const (
+	createAssets = `
+CREATE TABLE system.assets (
+    instance_id TEXT,
+    asset_type TEXT,
+    resource_owner TEXT,
+    name TEXT,
+    content_type TEXT,
+    hash TEXT AS (md5(data)) STORED,
+    data BYTES,
+    updated_at TIMESTAMPTZ,
+
+    PRIMARY KEY (instance_id, resource_owner, name)
+);
+`
+)
+
+type AssetTable struct {
+	dbClient *sql.DB
+}
+
+func (mig *AssetTable) Execute(ctx context.Context) error {
+	_, err := mig.dbClient.ExecContext(ctx, createAssets)
+	return err
+}
+
+func (mig *AssetTable) String() string {
+	return "02_assets"
+}