fix: reconnect immediately on app resume

[jcpsimmons]

Summary

• bypass reconnect backoff for explicit app-resume and network-online recovery
• preserve jittered backoff for ordinary disconnect retries
• add regression tests for immediate and normal reconnect timing

Why

reconnectNow() describes an immediate reconnect, but the reconnect-ticket refactor removed its immediate flag. Resume recovery therefore waits 800–1200 ms before opening a socket, long enough to show the 700 ms reconnecting overlay on every iOS foreground transition.

This restores the earlier immediate-resume behavior while keeping the newer reconnect-ticket caching logic.

Verification

• pnpm test (119 tests passed)
• pnpm typecheck
• pnpm exec biome check src/state/connection.ts src/state/reconnectDelay.ts src/state/reconnectDelay.test.ts
• iOS webpack bundle compiled successfully; the native archive step could not run in Linux because xcodebuild is unavailable