feat(video): Phase 12 streaming hardening

[keyldev]

• tile state machine: connecting/error overlays with Retry/Close, codec/res/fps/bitrate stats badge
• watchdog + exponential backoff (1-2-4-8-16-30s, reset on frame, cold->offline); fix concurrent FFmpeg init race (NRE in av_dict_set)
• smart pause on minimize with 10s grace + last-frame hold (no white flash)
• auto SD/HD: global toggle + layout policy + per-camera override (migration 007)
• WS-Discovery binds the chosen LAN NIC (ignores VPN/virtual); unit tests for backoff, quality policy, NIC selection

Summary

• tile state machine: connecting/error overlays with Retry/Close, codec/res/fps/bitrate stats badge
• watchdog + exponential backoff (1-2-4-8-16-30s, reset on frame, cold->offline); fix concurrent FFmpeg init race (NRE in av_dict_set)
• smart pause on minimize with 10s grace + last-frame hold (no white flash)
• auto SD/HD: global toggle + layout policy + per-camera override (migration 007)
• WS-Discovery binds the chosen LAN NIC (ignores VPN/virtual); unit tests for backoff, quality policy, NIC selection

Related

Type

• Bug fix
• Feature
• Refactor / cleanup
• Docs / CI
• Other:

Checklist

• Builds with 0 warnings (TreatWarningsAsErrors=true).
• Tests pass (dotnet test); new Core logic has unit tests.
• No layering violation — App references Core only (Infrastructure / Video / Devices wired via DI in a head).
• Scope stays within one phase (didn't pull work from a later phase's "Не входит").
• README / docs updated if public commands, options, or setup changed.

Platforms tested

• Windows
• Linux
• macOS
• Android
• iOS
• CI build only

Screenshots / notes