fix(session): resolve stuck 'No internet' status after network restore

[SERDUN]

Problem

After turning internet off and back on, the app status gets stuck on "Connection error" or "Connection issue" even though a fresh reconnect attempt is already in progress.

Observed on: Samsung SM-M325FV, Android 13
Log: samsung-SM-M325FV-Android-13_2026-04-10_130044.logcat

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Root Cause

__onSignalingClientEventConnecting in call_bloc.dart cleared only lastSignalingClientDisconnectError but left lastSignalingClientConnectError and lastSignalingDisconnectCode from the previous failed session:

// BEFORE — stale errors survive into the reconnect window
signalingClientStatus: SignalingClientStatus.connecting,
lastSignalingClientDisconnectError: null,
// lastSignalingClientConnectError ← NOT cleared
// lastSignalingDisconnectCode     ← NOT cleared

CallServiceState.get status evaluates these fields in priority order:

if (networkStatus == NetworkStatus.none)          → connectivityNone
else if (lastSignalingClientConnectError != null) → connectError   // ← stale error wins
else if (lastSignalingDisconnectCode != null)     → connectIssue   // ← stale code wins
...
else                                              → inProgress

So even when a fresh SignalingConnecting fires and the module is actively reconnecting, the UI shows "Connection error" or "Connection issue" until SignalingConnected clears them.

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Fix

Clear all stale error fields in __onSignalingClientEventConnecting:

// AFTER
signalingClientStatus: SignalingClientStatus.connecting,
lastSignalingClientConnectError: null,    // ← added
lastSignalingClientDisconnectError: null,
lastSignalingDisconnectCode: null,        // ← added

As soon as a new connect attempt starts, the status correctly reflects inProgress ("Connection in progress") for the entire reconnect window.

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Scope

• One handler in call_bloc.dart
• No model or API changes
• SignalingConnected already clears these fields — this fix mirrors that behavior one step earlier (at Connecting)

[Copilot]

Pull request overview

Fixes an incorrect UI connection status that could remain stuck on “Connection error/issue” after network recovery by clearing stale signaling error fields as soon as a new reconnect attempt begins, aligning Connecting behavior with the existing Connected cleanup.

Changes:

• Clear lastSignalingClientConnectError when a new SignalingClientStatus.connecting event is handled.
• Clear lastSignalingDisconnectCode when a new SignalingClientStatus.connecting event is handled.