Break up BLEManager.swift (2596 lines, 1756-line class body)

[kmatzen]

Problem

BLEManager.swift is at 2596 lines with a class body spanning 1756 lines. SwiftLint warns at 1000/800 respectively and errors at 2600. We're 4 lines from the error threshold — any new feature will trip it.

Suggested approach

Extract coherent sections into dedicated managers:

1. Command queue logic (~200 lines) — queueCommand, processCommandQueue, startCommandQueueTimer, rate limiting → BLECommandQueue.swift
2. Connection lifecycle (~300 lines) — connectToGoPro, disconnectFromGoPro, connectStaggered, straggler retry, scheduleReconnectIfNeeded → merge into existing BLEConnectionManager.swift
3. Sleep/power-down (~100 lines) — sendSleepCommand, sendPowerDownCommand, putCamerasToSleep, keep-alive timer → BLESleepManager.swift
4. Device query/scan timers (~80 lines) — startDeviceQueryTimer, startDeviceScanTimer → BLEPollingManager.swift
5. Settings sync (~150 lines) — sendSettings, sendSettingsToCamerasInGroup, queryAllSettings, verifySettings → BLESettingsManager.swift

Acceptance criteria

• BLEManager.swift under 800 lines (class body)
• No functional regressions — same behavior, same public API
• Each extracted manager gets its own unit test file