Improve Blazor reconnection experience after the server is restarted

[tomerqodo]

Benchmark PR from qodo-benchmark#32

[greptile-apps]

Greptile Summary

This PR improves the Blazor reconnection experience after server restart by implementing a graceful fallback mechanism. When the server loses circuit state (due to restart or expiration), the client now attempts to resume with a new circuit instead of immediately failing.

Key changes:

• Server no longer sends error messages when circuit state is unavailable, allowing the client to handle reconnection gracefully
• Client automatically attempts circuit resume after failed reconnection, creating a new session while preserving persisted state
• UI improvements: resume button now remains visible after resume failure, allowing users to retry without reloading
• Removed premature pause state updates during automatic reconnection flow
• Added comprehensive E2E tests validating reconnection behavior without server state

Issue found:

• DefaultReconnectDisplay.ts:119-123 - Missing line to hide rejoining animation when entering pause state, which could cause UI inconsistency

Confidence Score: 4/5

• This PR is generally safe to merge with one minor UI bug to fix
• The implementation is sound with good test coverage. However, there's a missing line in DefaultReconnectDisplay.ts that prevents the rejoining animation from being hidden during pause state, which could cause visual inconsistency in the UI. This is a minor issue that should be fixed but doesn't affect core functionality.
• Pay attention to src/Components/Web.JS/src/Platform/Circuits/DefaultReconnectDisplay.ts - missing animation hide statement

Important Files Changed

Filename	Overview
src/Components/Server/src/ComponentHub.cs	Removed error notification when circuit state cannot be retrieved, allowing client reconnection logic to handle the scenario gracefully
src/Components/Web.JS/src/Platform/Circuits/DefaultReconnectDisplay.ts	Improved UI state management by hiding buttons appropriately and allowing resume retry after failure
src/Components/Web.JS/src/Platform/Circuits/DefaultReconnectionHandler.ts	Removed premature pause UI update before resume attempt, improving reconnection flow
src/Components/test/E2ETest/ServerExecutionTests/ServerReconnectionWithoutStateTest.cs	Added comprehensive E2E tests validating reconnection behavior when server state is unavailable

Sequence Diagram

sequenceDiagram
    participant Client as Blazor Client
    participant Display as ReconnectDisplay
    participant Hub as ComponentHub (Server)
    
    Note over Client,Hub: Connection Lost Scenario
    
    Client->>Display: show(type: 'reconnect')
    Display->>Display: Hide resume/reload buttons
    Display->>Display: Show rejoining animation
    
    Client->>Hub: Attempt reconnect()
    alt Circuit state exists
        Hub-->>Client: Success (true)
        Client->>Display: hide()
        Note over Client,Display: Connection restored
    else Circuit state unavailable
        Hub-->>Client: Rejection (false)
        Note over Hub: No error sent to client
        Client->>Hub: Attempt resumeCircuit()
        alt Resume succeeds
            Hub-->>Client: Success (true)
            Client->>Display: hide()
            Note over Client,Display: Session resumed with new circuit
        else Resume fails
            Hub-->>Client: Rejection (false)
            Client->>Display: rejected()
            Display->>Client: location.reload()
            Note over Client,Display: Page reloads automatically
        end
    else Server unreachable
        Hub-->>Client: Exception
        Client->>Display: update() with retry countdown
        Note over Client,Display: Auto-retry with backoff
        Client->>Client: Retry after delay
    end
    
    Note over Client,Hub: Manual Pause Scenario
    
    Client->>Client: Blazor.pauseCircuit()
    Client->>Display: update(type: 'pause')
    Display->>Display: Hide rejoining animation
    Display->>Display: Show resume button
    
    User->>Display: Click Resume button
    Display->>Client: Trigger resume
    Client->>Hub: Attempt resumeCircuit()
    alt Resume succeeds
        Hub-->>Client: Success (true)
        Client->>Display: hide()
    else Resume fails
        Hub-->>Client: Rejection (false)
        Client->>Display: failed()
        Display->>Display: Show "retry or reload" message
        Display->>Display: Keep resume button visible
    end

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[greptile-apps]

_{9 files reviewed, 1 comment}

_{Edit Code Review Agent Settings | Greptile}

[greptile-apps]

logic: the rejoining animation should be hidden when entering pause state

Suggested change

	} else {
	this.reloadButton.style.display = 'none';
	this.rejoiningAnimation.style.display = 'none';
	this.status.innerHTML = 'The session has been paused by the server.';
	this.resumeButton.style.display = 'block';
	}
	} else {
	this.rejoiningAnimation.style.display = 'none';
	this.reloadButton.style.display = 'none';
	this.status.innerHTML = 'The session has been paused by the server.';
	this.resumeButton.style.display = 'block';

Prompt To Fix With AI

This is a comment left during a code review.
Path: src/Components/Web.JS/src/Platform/Circuits/DefaultReconnectDisplay.ts
Line: 119:123

Comment:
**logic:** the rejoining animation should be hidden when entering pause state

```suggestion
    } else {
      this.rejoiningAnimation.style.display = 'none';
      this.reloadButton.style.display = 'none';
      this.status.innerHTML = 'The session has been paused by the server.';
      this.resumeButton.style.display = 'block';
```

How can I resolve this? If you propose a fix, please make it concise.