Document Uri.Query and Uri.Fragment include leading delimiters (#12002)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: MihaZupan <25307628+MihaZupan@users.noreply.github.com>

Author: Copilot

xml/System/Uri.xml

@@ -2108,6 +2108,9 @@ If you used an escaped string to construct this instance (for example, `"http://
 
  The <xref:System.Uri.Fragment%2A> property is not considered in any <xref:System.Uri.Equals%2A> comparison.
 
+ > [!NOTE]
+ > The property includes the leading delimiter (`#`), whereas the URI specification (RFC 3986) recognizes the fragment as the portion of a URI without the delimiter.
+
 ## Examples
  The following example creates a <xref:System.Uri> instance and writes the fragment information to the console.
 
@@ -4218,6 +4221,9 @@ The following examples show a URI and the results of calling <xref:System.Uri.Ge
 
  For more information on IRI support, see the Remarks section for the <xref:System.Uri> class.
 
+ > [!NOTE]
+ > The property includes the leading delimiter (`?`), whereas the URI specification (RFC 3986) recognizes the query as the portion of a URI without the delimiter.
+
 ## Examples
  The following example writes the query `?date=today` to the console.