Fix SRTP type inference regression: ApplyDefaults now solves typars with MayResolveMember constraints

[Copilot]

Fixes SRTP type inference regression where curryN-style patterns worked in SDK 8.0 but failed with FS0030 (value restriction) in SDK 9.0+.

Root Cause

PR #15181 introduced FreshenTypar which clears StaticReq to None when InterfacesWithAbstractStaticMembers is enabled. SRTP typars retained their MayResolveMember constraints but lost the StaticReq marker that ApplyDefaults relied on to identify them.

Fix

Extended ApplyDefaults in CheckDeclarations.fs to explicitly check for MayResolveMember constraints:

let hasSRTPConstraint = 
    tp.Constraints |> List.exists (function TyparConstraint.MayResolveMember _ -> true | _ -> false)
    
if (tp.StaticReq <> TyparStaticReq.None) || hasSRTPConstraint then
    ChooseTyparSolutionAndSolve cenv.css denvAtEnd tp

This ensures SRTP typars are solved regardless of whether StaticReq is preserved through freshening.

Verification

• Added regression test for curryN-style SRTP patterns
• FSharpPlus test suite integration confirms the fix
• No regressions in existing SRTP tests

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