Fix app doesn't go into reconnection mode in some cases

[dimadesu]

Root cause — two problems combining to suppress reconnection:

1. Race condition (CameraStreamerService sets NOT_STREAMING ~4ms before isStreamingFlow emits false). The old code read streamStatus.value as previousStatus, so by the time the isStreamingFlow observer fired, the status was already NOT_STREAMING → wasStreaming = false → reconnect skipped silently.

2. Silent socket close — when you turn WiFi off in Android Settings, the OS closes the SRT UDP socket cleanly (no error), so no ClosedException is emitted to throwableFlow. The isStreamingFlow observer was the only remaining reconnect path — but bug Foreground service #1 broke it.

Fix — in the isStreamingFlow observer, replaced the unreliable previousStatus check with a var previouslyStreaming local variable that tracks the actual previous value of the flow itself. It's initialized from isStreamingFlow.value (handles already-streaming case on attach), set to true when isStreaming=true fires, used as wasStreaming when isStreaming=false fires, then reset to false. This is completely independent of the service's status updates, so the race condition can no longer suppress reconnection.

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The diff is clean and minimal. Let me analyze potential behavioral changes:

Scenarios that now work differently:

Scenario	Old behavior	New behavior	Concern?
WiFi off → SRT socket silently closed	wasStreaming=false → no reconnect	wasStreaming=true → reconnect triggers	Desired fix
Service observer fires NOT_STREAMING before isStreamingFlow=false	Race → reconnection suppressed	Race irrelevant, tracked independently	Desired fix

Scenarios that remain unchanged:

1. User taps Stop — userStoppedManually=true is set before anything else happens, so the wasStreaming check never reaches the reconnect branch. No change.

2. Already reconnecting — isReconnecting=true guard remains, prevents duplicate triggers. No change.

3. Stream that never started (isStreamingFlow was never true) — previouslyStreaming initializes from isStreamingFlow.value which is false, and is never set to true, so wasStreaming=false → goes to "Stream never started" path. No change.

4. Service rebind after process death — previouslyStreaming re-initializes from current isStreamingFlow.value. If the stream was running, it picks up true; if not, false. Same semantics as before.

One edge case worth noting:

If isStreamingFlow emits true → false → false rapidly (e.g., flicker), the first false sets previouslyStreaming = false, so the second false correctly gets wasStreaming=false. No double-reconnect. Safe.

Verdict: The fix is safe. The only behavioral change is that the reconnection now correctly triggers when WiFi drops silently — no other paths are affected.