refactor: convert to bun workspaces monorepo

- Move web app into apps/web/
- Create packages/shared/ with shared types
- Create plugins/decky-vault/ scaffold
- Root package.json manages workspaces only

apps/web/drizzle/0020_flaky_lilith.sql

@@ -0,0 +1,3 @@
+ALTER TABLE "community_suggestions" DROP CONSTRAINT "community_suggestions_reviewed_by_user_id_fk";
+--> statement-breakpoint
+ALTER TABLE "community_suggestions" ADD CONSTRAINT "community_suggestions_reviewed_by_user_id_fk" FOREIGN KEY ("reviewed_by") REFERENCES "public"."user"("id") ON DELETE set null ON UPDATE no action;