fix: mobile UI — input layout, sidebar overlap, session switch independence

[PureWeen]

Purely mobile fixes, split from #487.

Changes

• Bridge session switch independence — mobile SwitchSession no longer changes desktop's active session
• Compact input layout — mode switcher (Chat/Plan/Autopilot) condensed to dropdown on mobile, smaller textarea, status bar extras hidden
• Sidebar filter bar overlap fixed — Attention/All/Idle bar no longer floats over session list in mobile flyout

Desktop is untouched — all CSS changes are inside @media (max-width: 640px) or scoped to .mobile-flyout-sidebar.

[PureWeen]

🤖 Multi-Model Code Review — R1 (PR #498)

CI Status: ℹ️ No CI checks configured
Prior comments: None (fresh review)

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Summary

Mobile UI improvements: bridge session switch independence, compact input layout with mode dropdown, sidebar flyout overlap fix, Android keyboard handling, and restored log/prompts in status bar.

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🔴 CRITICAL — Test assertion null bug

File: PolyPilot.Tests/WsBridgeIntegrationTests.cs:1108
Flagged by: 3/3 reviewers

Assert.NotEqual("switch-b", _copilot.GetActiveSession()?.Name ?? "switch-b");

If GetActiveSession() returns null, ?.Name → null, ?? "switch-b" → "switch-b". The assertion becomes NotEqual("switch-b", "switch-b") → misleading failure that looks like the old bug is present when actually the session was lost entirely.

Additionally, the assertion is too weak — it passes trivially because "switch-a" was already the active session before the switch. It should positively assert the active session stayed as "switch-a":

Assert.Equal("switch-a", _copilot.GetActiveSession()?.Name);

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🟡 MODERATE — AdjustResize deprecated on API 30+ / edge-to-edge conflict

File: PolyPilot/Platforms/Android/MainActivity.cs:12
Flagged by: 3/3 reviewers

SoftInput.AdjustResize is deprecated on Android 11+ (API 30) and may not resize the WebView in edge-to-edge mode on modern devices. The repo instructions note edge-to-edge is the .NET 10 MAUI default and insets are handled in CSS/JS. This may work correctly on the test device but could fail on API 30+ with gesture navigation.

Recommendation: Test on an API 30+ device. If the keyboard still obscures content, consider visualViewport API or env(keyboard-inset-height) instead.

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🟡 MODERATE — BroadcastSessionsList sends desktop active session to mobile

File: PolyPilot/Services/WsBridgeServer.cs (SwitchSession handler)
Flagged by: 3/3 reviewers

After removing SetActiveSession, the BroadcastSessionsList() call still sends ActiveSession = _copilot.ActiveSessionName (the desktop's active session) to all clients. Mobile WsBridgeClient updates ActiveSessionName from this broadcast. If mobile UI reads ActiveSessionName to highlight the current session, it will immediately revert to the desktop's view after switching.

Recommendation: Consider removing BroadcastSessionsList() from the SwitchSession handler (no list state actually changed), or tracking per-client active session separately.

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🟡 MODERATE — Blazor select null propagation

File: PolyPilot/Components/ExpandedSessionView.razor
Flagged by: 2/3 reviewers

<select ... @onchange="e => OnSetInputMode.InvokeAsync(e.Value?.ToString())">

e.Value is object? — if the browser sends an empty or unrecognized value, null propagates to OnSetInputMode. Should fall back to current mode:

@onchange="e => OnSetInputMode.InvokeAsync(e.Value?.ToString() ?? InputMode)"

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Test Coverage

• ✅ SwitchSession_BroadcastsUpdatedActiveSession updated for new behavior
• ⚠️ Test assertion has null-safety bug (see CRITICAL above)
• ⚠️ No test for history delivery after mobile switch (the positive path of the new behavior)

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Verdict: ⚠️ Request Changes

1. Fix test assertion — use Assert.Equal("switch-a", _copilot.GetActiveSession()?.Name) instead of the null-coalescing NotEqual
2. Null-guard the select — add ?? InputMode fallback
3. Consider removing BroadcastSessionsList() from SwitchSession handler (no state changed)
4. Verify AdjustResize on API 30+ device — may need alternative approach for modern Android