Apply freshness tiers to the Csharp update cycle (#48005)

* first pass at C# freshness

* Finalize freshness tiers for C#

* Apply suggestions from code review

* Update docfx.json

Co-authored-by: Genevieve Warren <[email protected]>

---------

Co-authored-by: Genevieve Warren <[email protected]>

Author: BillWagner

docfx.json

@@ -907,8 +907,18 @@
             },
             "ms.update-cycle": {
                 "docs/ai/**/**.{md,yml}": "180-days",
-                "docs/csharp/whats-new/**/**.{md,yml}": "1825-days",
-                "docs/framework/**/**.{md,yml}": "3650-days",
+                "docs/csharp/whats-new/**/**.{md,yml}": "1095-days",
+                "docs/csharp/advanced-topics/interop/**/**.{md,yml}": "1825-days",
+                "docs/csharp/advanced-topics/reflection-and-attributes/**/**.{md,yml}": "1825-days",
+                "docs/csharp/fundamentals/exceptions/**/**.{md,yml}": "1825-days",
+                "docs/csharp/language-reference/**/**.{md,yml}": "1095-days",
+                "docs/csharp/language-reference/compiler-messages/**/**.{md,yml}": "3650-days",
+                "docs/csharp/language-reference/xmldoc/**/**.{md,yml}": "3650-days",
+                "docs/csharp/linq/**/**.{md,yml}": "1825-days",
+                "docs/csharp/misc/**/**.{md,yml}": "3650-days",
+                "docs/csharp/roslyn-sdk/**/**.{md,yml}": "1825-days",
+                "docs/csharp/specification/**/**.{md,yml}": "1825-days",
+                "docs/framework/**/*.md": "3650-days",
                 "docs/iot/**/**.{md,yml}": "1825-days",
                 "docs/visual-basic/**/**.{md,yml}": "3650-days"
             },