Fix access checking for properies setters in attribute arguments

[evgTSV]

Description

Fixes #18571

I use checking from MethInfoChecks

Checklist

• Test cases added
• Release notes entry updated:

[github-actions]

❗ Release notes required

@evgTSV,

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Change path	Release notes path	Description
src/Compiler	docs/release-notes/.FSharp.Compiler.Service/10.0.100.md	No release notes found or release notes format is not correct

[Copilot]

Pull Request Overview

This PR enhances attribute argument validation by enforcing accessibility checks on property setters when used in attribute targets.

• Retrieves the setter method and checks its accessibility using existing MethInfoChecks logic.
• Emits a distinct error (tcPropertyCannotBeSet1) if the setter exists but isn’t accessible.
• Integrates the new check into the Item.Property branch of TcAttributeEx.

Comments suppressed due to low confidence (2)

src/Compiler/Checking/Expressions/CheckExpressions.fs:11414

• [nitpick] Consider renaming setterMeth to setterMethod for clarity and consistency with other method-related variables.

let setterMeth = pinfo.SetterMethod

src/Compiler/Checking/Expressions/CheckExpressions.fs:11414

• Add unit tests covering this new setter accessibility check in attribute arguments to prevent regressions and validate both allowed and disallowed cases.

let setterMeth = pinfo.SetterMethod

[vzarytovskii]

Is it the same as #18575?

[evgTSV]

@vzarytovskii I don't think #18575 can solve this problem, I looked into the code of the IsPropInfoAccessible function, it only defines access to the property getter, so I used the code from checking the property during the processing of the constructors args of a type that is not an attribute

[evgTSV]

Ok, I can close this pr and go to #18575

[vzarytovskii]

Ok, I can close this pr and go to #18575

It's fine to process here, I was just curious whether it overlaps or not. I can close that one down and you can incorporate changes into one/this one. Conversing with copilot is a bit tiresome.

[evgTSV]

It's fine to process here, I was just curious whether it overlaps or not. I can close that one down and you can incorporate changes into one/this one. Conversing with copilot is a bit tiresome.

Yeah, I'll work on this pr then

[T-Gro]

For sure carry on, please consider the currently open copilot PRs more of an exercise of the capabilities - pick anything good from there and we can close it down and keep yours only :)

[evgTSV]

@dotnet-policy-service agree