chore: changeset for studio developer UX overhaul (patch)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: os-zhuang

.changeset/studio-developer-ux.md

@@ -0,0 +1,15 @@
+---
+"@objectstack/studio": patch
+"@objectstack/client": patch
+---
+
+Studio developer UX overhaul.
+
+- **Inspector drawer** (right Sheet, toggle via header button or `]`) with API / Source / Refs tabs that auto-populate from the current resource detail page.
+- **Problems panel** (status bar pill + `[`) that subscribes to object/view/flow/hook changes and surfaces unknown object refs, missing field refs, and broken triggers with deep-links back to source.
+- **Keyboard shortcuts**: `g o|f|v|a|s|p` navigation, `[` problems, `]` inspector, `?` help dialog.
+- **Resource actions menu** (`⋯` on detail page header): Copy as curl / fetch() / `defineX()` TypeScript / Metadata JSON; Open in VS Code; Open API endpoint.
+- **Welcome onboarding** empty-state in the developer overview when a package has no metadata.
+- New `StudioShell` wrapper; `TopBar` gains a `rightSlot` prop for Inspector / Help buttons.
+
+`@objectstack/client`: surface plain-string `error` bodies (e.g. `RECORD_LOCKED: …`) in fetch error messages instead of swallowing them as `Bad Request`.