[Refactor/#80] ControlBox 커스터마이징, WorkspaceSetting 삭제영역 구조 통일 - #82

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@src/components/common/controlbox/ControlBox.tsx`:
- Around line 32-33: The exposed prop buttonSize on ControlBox is being
overridden by a hardcoded height utility (!h-button-big) in the rendered class
list, so size changes have no effect; update the ControlBox render logic to
remove the fixed "!h-button-big" and instead apply height/size classes
conditionally based on the buttonSize prop (e.g., map "small"|"medium"|"large"
to the appropriate classes) so the prop actually controls the button height;
adjust any related classname generation where "!h-button-big" appears (and
similarly for the other occurrence) to reference the new size-to-class mapping
used by the component.

In `@src/pages/workspace/WorkspaceSetting.tsx`:
- Around line 216-229: The delete flow button (ControlBox with title "워크스페이스
삭제") is currently clickable during a save, which allows concurrent save+delete
requests; wire the same disabling condition used for save into this control by
passing the appropriate disabled/disabledButton prop (or the ControlBox's
equivalent) so the delete button is disabled whenever saving || deleting is
true; update the ControlBox usage that currently has
onButtonClick={openDeleteModal} to include the disable flag tied to the existing
saving and deleting state variables so the button cannot be activated during
saves or while deletion is in progress.