Breakpoints page: enabled state not synced with server

[phaser]

Bug

In PR #314 (Breakpoint UI), the breakpointsEnabled state on the Breakpoints page is derived from rules.Count > 0 in RefreshAll():

breakpointsEnabled = rules.Count > 0;

This means:

1. If rules exist but breakpoints are disabled at the server level, the UI incorrectly shows "Enabled"
2. Toggling breakpoints calls EnableBreakpointsAsync()/DisableBreakpointsAsync() on the API, but after a page refresh the state is re-derived from rule count, not the actual server state

Expected Behavior

The breakpointsEnabled state should reflect the actual enabled/disabled state from the server, not be inferred from rule count.

Suggested Fix

Add a GET /api/breakpoints/status endpoint (or include enabled state in the rules response) and use that to initialize breakpointsEnabled.

Severity

Medium — Users could be confused about whether breakpoints are actually active.

Found during QA review of PR #314.