TryFindMethod returns false for methods an interface inherits from its base interfaces: typeof(IList<int>).TryFindMethod("Add", …) finds nothing #158

What's wrong

ReflectionExtensions.TryFindMethod (Extensions/ReflectionExtensions.cs:30-38) climbs the type hierarchy through Type.BaseType. An interface type's BaseType is always null, and Type.GetMethod on an interface does not search the interfaces it extends. So when type is an interface, the search covers only the interface's own declared members. Every method inherited from a base interface is reported as missing, even though the doc comment says the method "walks up the inheritance tree".

Reproduction (run against a local build, net10.0)

using System.Reflection;
using ktsu.Extensions;

public interface IBase { void BaseOp(); }
public interface IDerived : IBase { }

var flags = BindingFlags.Public | BindingFlags.Instance;
typeof(IDerived).TryFindMethod("BaseOp", flags, out var m1);          // false, m1 == null
typeof(IList<int>).TryFindMethod("Add", flags, out var m2);           // false (Add is declared on ICollection<T>)
typeof(IList<int>).TryFindMethod("GetEnumerator", flags, out var m3); // false (declared on IEnumerable<T>)
typeof(ICollection<int>).TryFindMethod("Add", flags, out var m4);     // true

Observed output:

IList`1.GetEnumerator: False
ICollection`1.Add: True ICollection`1
IList`1.Add: False
IDerived.BaseOp: False

Expected: true in all four cases, with methodInfo pointing at the method on the interface that declares it.

Why it matters

Code that discovers members by convention is often handed an interface type, such as a service contract or typeof(IList<T>). For those types the method returns false for members that do exist. Because this is a Try method, the caller reads false as "not present" and silently skips the member or takes a fallback path, with no error to point at the cause. The existing tests in ReflectionExtensionsTests.cs cover class inheritance only.

Suggested fix / acceptance criteria

• When type.IsInterface and no match is found on type itself, also search type.GetInterfaces(), which returns every inherited interface.
• All four repro lines above return true, and methodInfo.DeclaringType is the interface that declares the method.
• Add a test with a two-level interface hierarchy. If TryFindMethod throws AmbiguousMatchException for overloaded method names instead of returning a result #155 (overload ambiguity) is fixed first, the interface search should use the same overload-resolution rule.