fix(streaming): preserve ADO.NET dequeue order

[ReubenBond]

Fixes #10522.
Fixes #10458.

The ADO.NET stream pulling agent uses the first message returned for each stream as the cache cursor. MySQL selects dequeue batches in MessageId order but returns the joined rows without an ordering guarantee. PostgreSQL has the same issue because UPDATE ... RETURNING does not preserve the CTE's selection order. In preserved CI failures, affected streams produced all ten items but consumption began at sequential#2, skipping the older first row which had been returned later in the result set.

This change orders the MySQL procedure result and normalizes all ADO.NET dequeue results by MessageId, protecting existing database schemas and every provider whose result ordering is not guaranteed. It also adds a deterministic regression which supplies reverse-ordered provider results and strengthens batch coverage with concurrent enqueues.

Microsoft Reviewers: Open in CodeFlow

[Copilot]

Pull request overview

Fixes ADO.NET streaming dequeue ordering by ensuring GetStreamMessagesAsync returns results ordered by MessageId, addressing a MySQL-specific flake where unordered joined rows could cause the cache cursor to advance incorrectly and skip earlier items.

Changes:

• Normalize all ADO.NET dequeue results by sorting GetStreamMessagesAsync results by MessageId.
• Add/extend MySQL-focused regression coverage to validate ordering and increase batch coverage with concurrent enqueues.
• Ensure the MySQL streaming dequeue procedure returns its batch in MessageId order.

Show a summary per file

File	Description
test/Extensions/Orleans.AdoNet.Tests/Streaming/RelationalOrleansQueriesTests.cs	Adds a MySQL regression test for provider-result ordering and strengthens dequeue-batch coverage using concurrent enqueues.
src/AdoNet/Shared/Storage/RelationalOrleansQueries.cs	Sorts dequeued stream messages by MessageId to make result ordering deterministic across providers.
src/AdoNet/Orleans.Streaming.AdoNet/MySQL-Streaming.sql	Adds ORDER BY M.MessageId to the MySQL dequeue procedure’s returned result set to preserve dequeue order.

Review details

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Suppressed comments (1)

test/Extensions/Orleans.AdoNet.Tests/Streaming/RelationalOrleansQueriesTests.cs:422

• This test now queues 100 messages concurrently without any throttling. For MySQL specifically, this test class is configured with a lower concurrency value, and other tests in this file explicitly gate parallel DB calls to avoid connection pool timeouts. Throttle these enqueues to concurrency to reduce flakiness.

        var acks = await Task.WhenAll(Enumerable
            .Range(0, total)
            .Select(i => _queries.QueueStreamMessageAsync(serviceId, providerId, queueId, payload, expiryTimeout))
            .ToList());

• Files reviewed: 3/3 changed files
• Comments generated: 2
• Review effort level: Lite

[Copilot]

Review details

• Files reviewed: 3/3 changed files
• Comments generated: 0 new
• Review effort level: Lite