feat(strawberry-shake): persist IOperationResult via [PersistentState] (.NET 10)

[cliedeman]

Summary

A declarative way to persist StrawberryShake results across the Blazor prerender → interactive boundary (related to ChilliCream#7209), using the .NET 10 [PersistentState] attribute directly on an IOperationResult<T> property. No generated UseQuery-style component (cf. the companion PR), and — as of the latest commit — no per-type registration:

// Program.cs — the generated client registers the serializers for you
builder.Services.AddFooClient(...);

// Component
[PersistentState]
public IOperationResult<IGetMeResult>? Result { get; set; }

protected override async Task OnInitializedAsync()
    => Result ??= await HubClient.GetMe.ExecuteAsync(CancellationToken.None);

On prerender Result is persisted; on the interactive client it's restored without re-executing the operation; the ??= skips the call. Opt in with "razorPersistedState": true in .graphqlrc.json (requires a store and a reference to StrawberryShake.Razor).

How it works

.NET 10 allows a custom serializer to be plugged into [PersistentState] via PersistentComponentStateSerializer<T> (a DI singleton). This sidesteps the interface-serialization wall: the serializer persists the raw transport data payload and rebuilds via the operation's result builder.

• OperationResultBuilder captures the raw data element into ContextData (gated by the CapturePersistedData virtual) and rebuilds a result from a persisted payload via BuildFromPersistedData. IOperationResultBuilder exposes BuildFromPersistedData as a throwing default-interface-method (non-JSON transports unaffected).
• OperationResultPersistentStateSerializer<TData> (StrawberryShake.Razor, #if NET10_0_OR_GREATER): Persist writes the captured payload; Restore rebuilds it through the result builder.
• Generated wiring (opt-in razorPersistedState): the result builders emit CapturePersistedData => true, and the generated AddFooClient() registers, per result type and behind #if NET10_0_OR_GREATER, AddSingleton<PersistentComponentStateSerializer<IOperationResult<T>>, OperationResultPersistentStateSerializer<T>>(). All registrations reuse the single generic serializer class as singletons. AddPersistentOperationResult<TData>() remains available for manual/edge cases.

Trade-offs vs the UsePersistentQuery approach

• More idiomatic and lighter: no generated component, standard .NET 10 declarative pattern, the consumer owns the component.
• .NET 10+ only (the serializer and the generated registration are #if-guarded; net8/9 consumers compile with the registration excluded).
• Snapshot, not reactive: Result is a one-time value (no Watch/store-update reactivity), which is the typical need for prerender hydration.

Tests

• StrawberryShake.Razor.Tests (net10/net11): serializer Persist/Restore round-trip (no re-execution) and the empty-data fallback.
• Core.Tests: capture into ContextData and BuildFromPersistedData round-trip.
• Razor codegen snapshot: the emitted #if-guarded serializer registration and the CapturePersistedData override.
• Client and CodeGeneration solutions build across net8.0/net9.0/net10.0/net11.0.

🤖 Generated with Claude Code