chore(changeset): patch for the never-residual collections comment

Claude-Session: https://claude.ai/code/session_01JQwxbad6xiDCcLYXcBsEa6
Co-authored-by: Claude <noreply@anthropic.com>

Author: claude

.changeset/29335-residual-datasets-docblock.md

@@ -0,0 +1,10 @@
+---
+'@objectstack/spec': patch
+---
+
+docs(spec): the comment on the stack's never-residual collections names the readers that exist
+
+Clause-②: no
+Metadata-protocol: none
+
+A comment-only change in `src/stack.zod.ts`, which the package ships as source. The comment on the set of top-level collections a `packages[]` stack never treats as residual (`data`, `datasets`, `jobs`) said `AppPlugin` consumes top-level `datasets` straight off the bundle. It does not: a package body's `datasets` are read by the engine's `registerApp` (`@objectstack/objectql`), and no boot reader takes a top-level `datasets` item that no body declares. The comment now says so. No schema, type, export or behaviour changes; nothing to migrate.