Enable swipe comparison by default in Interactive Labeler

[calebrob6]

Problem Statement

The Interactive Labeler currently requires analysts to open Advanced options and enable the pre/post-event swipe map before they can compare imagery. This adds friction to a core labeling workflow.

Proposed Solution

Enable Swipe (pre-event) by default when the Interactive Labeler opens. Keep the existing toggle so users can disable and re-enable swipe comparison. Preserve pre-event imagery on the left, post-event imagery on the right, and the existing A / S / D divider shortcuts.

Acceptance Criteria

• Swipe comparison is enabled when the Interactive Labeler finishes loading.
• Pre-event imagery (or the basemap fallback) appears on the left and post-event imagery appears on the right.
• The Advanced toggle accurately reflects the enabled state.
• Users can disable and re-enable swipe without losing labels or map interaction.
• A, S, and D continue to move the divider left, center, and right.

Related Work

• [Feature]: Document (and maybe standardize) hotkeys across map views #47
• Let me see misclassified buildings #100