feat(cloud): write worspace slug availability checks to db

packages/db/migrations/20250910200416_AddWorkspaceSlugChecks.sql

@@ -0,0 +1,22 @@
+CREATE TABLE IF NOT EXISTS "workspace_slug_checks" (
+	"id" bigserial PRIMARY KEY NOT NULL,
+	"slug" varchar(255) NOT NULL,
+	"available" boolean NOT NULL,
+	"reserved" boolean NOT NULL,
+	"workspaceId" bigint,
+	"createdBy" uuid,
+	"createdAt" timestamp DEFAULT now() NOT NULL
+);
+--> statement-breakpoint
+ALTER TABLE "workspace_slug_checks" ENABLE ROW LEVEL SECURITY;--> statement-breakpoint
+DO $$ BEGIN
+ ALTER TABLE "workspace_slug_checks" ADD CONSTRAINT "workspace_slug_checks_workspaceId_workspace_id_fk" FOREIGN KEY ("workspaceId") REFERENCES "public"."workspace"("id") ON DELETE no action ON UPDATE no action;
+EXCEPTION
+ WHEN duplicate_object THEN null;
+END $$;
+--> statement-breakpoint
+DO $$ BEGIN
+ ALTER TABLE "workspace_slug_checks" ADD CONSTRAINT "workspace_slug_checks_createdBy_user_id_fk" FOREIGN KEY ("createdBy") REFERENCES "public"."user"("id") ON DELETE set null ON UPDATE no action;
+EXCEPTION
+ WHEN duplicate_object THEN null;
+END $$;