Adds :key="component" to <component :is="Body"> so opening drawer B
while A is open fully remounts (A's instance/state can't leak into B) —
a real defect for a primary shell overlay. Same-name reopen still
relies on the body reacting to prop changes (documented inline).
Companion test asserts the cross-component switch swaps the body
cleanly (A unmounts, B mounts). Addresses the Task 5 code-review
Important finding.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
bert.hausmans
ca0332d17a