[compiler] Resolve members through template parameters.

.chronus/changes/witemple-msft-templateparameter-metaproperties-2026-2-2-13-17-55.md

@@ -0,0 +1,17 @@
+---
+changeKind: feature
+packages:
+  - "@typespec/compiler"
+---
+
+Enabled resolution of member properties and metaproperties through template parameters based on constraints.
+
+```tsp
+model Resource {
+  id: string;
+}
+
+model Read<R extends Resource> {
+  id: R.id;
+}
+```

.chronus/changes/witemple-msft-templateparameter-metaproperties-2026-2-2-15-5-30.md

@@ -0,0 +1,9 @@
+---
+changeKind: internal
+packages:
+  - "@typespec/html-program-viewer"
+  - "@typespec/http-server-csharp"
+  - "@typespec/tspd"
+---
+
+Updated some packages to account for introduction of new TemplateParameterAccess virtual type.