Simplify flag checks throughout libraries

[Copilot]

Description

Simplifies flag checking patterns that can be combined into single bitwise operations, improving code generation as described in issue #93954.

Patterns simplified:

• OR checks: (flags & A) != 0 || (flags & B) != 0 → (flags & (A | B)) != 0
• AND checks: x.HasFlag(A) && x.HasFlag(B) → (x & (A | B)) == (A | B)
• Has A but not B: (x & A) != 0 && (x & B) == 0 → (x & (A | B)) == A

Files changed:

• Uri.cs: Combined CompressPath | ConvertPathSlashes | UnEscapeDotsAndSlashes check; simplified 4 InFact/NotAny combinations
• XmlSchemaValidator.cs: Combined ProcessInlineSchema | ProcessSchemaLocation check
• NegotiateAuthenticationPal.ManagedNtlm.cs: Simplified NegotiateSign && NegotiateKeyExchange assertion
• UpgradeToGeneratedRegexCodeFixer.cs: Simplified IgnoreCase && !CultureInvariant check
• Number.Parsing.Common.cs: Simplified StateSign && !StateCurrency check
• Test files: FakeNtlmServer.cs, DynamicRevocationTests.cs, TypeBuilderDefineNestedType.cs

Example:

// Before
if (InFact(Flags.E_PathNotCanonical) && NotAny(Flags.UserEscaped))

// After  
if ((_flags & (Flags.E_PathNotCanonical | Flags.UserEscaped)) == Flags.E_PathNotCanonical)

Original prompt

The checks in

runtime/src/libraries/System.Private.Uri/src/System/Uri.cs

Lines 3305 to 3306 in c78b335

	(((syntaxFlags & (UriSyntaxFlags.CompressPath | UriSyntaxFlags.ConvertPathSlashes)) != 0) ||
	(syntaxFlags & UriSyntaxFlags.UnEscapeDotsAndSlashes) != 0)))

are testing a pattern along the lines of
if ((flags & (Flags.A | Flags.B)) != 0 || (flags & Flags.C) != 0)
this can be simplified to just
if ((flags & (Flags.A | Flags.B | Flags.C)) != 0

Fix that occurance as well as any other place throughout libraries where flag checks could be combined together

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[MihaZupan]

@MihuBot