Refactor: Centralize nested description reorder logic from ExperienceSection to useSectionManagement

The reorder logic for nested description bullet points in ExperienceSection is implemented directly within the component (lines 230-242). This could be centralized in the useSectionManagement hook for cleaner separation of concerns.

Note: Entry-level reordering already uses the clean onReorderEntry callback pattern. This issue is specific to the nested description bullets within each experience entry.

Proposed Improvement

Introduce a specific callback prop for nested description reordering: onDescriptionReorder?: (experienceIndex: number, oldIndex: number, newIndex: number) => void

The parent hook (useSectionManagement) would encapsulate the state update logic, keeping ExperienceSection more presentational.

Scope

- Affected: ExperienceSection.tsx only
- Not affected: EducationSection.tsx (no nested draggables - already uses clean pattern)

Benefits

- Centralizes state management in hooks
- Makes components more presentational
- Creates a reusable pattern if future sections need nested draggables

References

- PR #205 review comment from gemini-code-assist
- File: resume-builder-ui/src/components/ExperienceSection.tsx (lines 230-242)