Update logging source generator docs for generic method support, SYSLIB1028, and SYSLIB1029

[Copilot]

Reflects two runtime changes to the LoggerMessageAttribute source generator:

• dotnet/runtime#124638: Generic logging methods are now fully supported; SYSLIB1011 narrows from "cannot be generic" to "cannot use the allows ref struct anti-constraint"
• dotnet/runtime#124589: params and scoped modifiers are now explicitly diagnosed as SYSLIB1028; ref struct parameter types as SYSLIB1029; ref readonly is now correctly preserved

Changes

• syslib1011.md — Updated title, description, and workaround to reflect the narrowed restriction (allows ref struct only)
• syslib1028.md (new) — Documents SYSLIB1028: params and scoped modifiers unsupported on logging method parameters
• syslib1029.md (new) — Documents SYSLIB1029: ref struct types unsupported as logging method parameters
• source-generator-overview.md — SYSLIB1011 entry updated; SYSLIB1028/1029 promoted from reserved placeholders to real entries with links
• source-generation.md — "Log method constraints" updated to reflect all changes: generics now valid (except allows ref struct), params/scoped/out forbidden, ref struct forbidden, ref readonly supported

What's now valid / invalid

// ✅ Now works — generic method with value-type constraint
[LoggerMessage(0, LogLevel.Trace, "Channel {Channel}: code {Code}")]
public static partial void LogPacket<TCode>(
    ILogger logger, string channel, TCode code)
    where TCode : struct, Enum;

// ✅ Now works — ref readonly parameter (modifier is preserved)
[LoggerMessage(1, LogLevel.Debug, "Value: {Value}")]
public static partial void LogValue(ILogger logger, ref readonly int value);

// ❌ SYSLIB1011 — allows ref struct anti-constraint still blocked
[LoggerMessage(2, LogLevel.Debug, "Value: {Value}")]
public static partial void LogRef<T>(ILogger logger, T value)
    where T : allows ref struct;

// ❌ SYSLIB1028 — params and scoped modifiers blocked
// ❌ SYSLIB1029 — ref struct parameter types blocked

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Internal previews

📄 File	🔗 Preview link
docs/core/extensions/logging/source-generation.md	docs/core/extensions/logging/source-generation
docs/fundamentals/syslib-diagnostics/source-generator-overview.md	docs/fundamentals/syslib-diagnostics/source-generator-overview
docs/fundamentals/syslib-diagnostics/syslib1011.md	docs/fundamentals/syslib-diagnostics/syslib1011
docs/fundamentals/syslib-diagnostics/syslib1028.md	docs/fundamentals/syslib-diagnostics/syslib1028
docs/fundamentals/syslib-diagnostics/syslib1029.md	docs/fundamentals/syslib-diagnostics/syslib1029

[Copilot]

Pull request overview

This PR updates the logging source generator documentation to reflect two significant runtime changes in .NET. The changes narrow SYSLIB1011 from blocking all generic methods to only blocking the allows ref struct anti-constraint, and introduce two new diagnostic codes (SYSLIB1028 and SYSLIB1029) for previously undiagnosed parameter restrictions.

Changes:

• SYSLIB1011 narrowed: generic logging methods now supported, except when using the C# 13 allows ref struct anti-constraint
• Two new diagnostics added: SYSLIB1028 for params/scoped modifiers and SYSLIB1029 for ref struct parameter types
• Log method constraints updated to reflect the expanded support for generics and explicit restrictions

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
docs/fundamentals/syslib-diagnostics/syslib1011.md	Updated to reflect narrowed scope - only blocks allows ref struct constraint, not all generics
docs/fundamentals/syslib-diagnostics/syslib1028.md	New diagnostic documentation for unsupported params and scoped parameter modifiers
docs/fundamentals/syslib-diagnostics/syslib1029.md	New diagnostic documentation for ref struct parameter types
docs/fundamentals/syslib-diagnostics/source-generator-overview.md	Updated table entries for SYSLIB1011, promoted SYSLIB1028/1029 from reserved to documented
docs/core/extensions/logging/source-generation.md	Updated constraints section to reflect generic support and explicit modifier/type restrictions

[Copilot]

The title wording is inconsistent with SYSLIB1024, which uses "the unsupported" instead of "an unsupported". For consistency, consider changing to: "Argument is using the unsupported 'params' or 'scoped' parameter modifier" to match the pattern used in SYSLIB1024.

Suggested change

	f1_keywords:
	- SYSLIB1028
	---
	# SYSLIB1028: Argument is using an unsupported parameter modifier
	ai-usage: ai-assisted
	f1_keywords:
	- SYSLIB1028
	---
	# SYSLIB1028: Argument is using the unsupported 'params' or 'scoped' parameter modifier

[Copilot]

The f1_keywords value uses lowercase "syslib1011", but newer SYSLIB diagnostic files use uppercase (e.g., "SYSLIB1024", "SYSLIB1028", "SYSLIB1029"). For consistency with the newer convention, consider changing this to "SYSLIB1011".

Suggested change

	- syslib1011
	- SYSLIB1011