fix(api): generate string ID parameters for meters

Signed-off-by: Mark Sagi-Kazar <[email protected]>

api/spec/src/meters.tsp

@@ -194,7 +194,7 @@ enum WindowSize {
 /**
  * A unique meter identifier.
  */
-alias MeterIdentifier = ULID | Key;
+alias MeterIdentifier = ULIDOrKey;
 
 /**
  * Meter query parameters.

api/spec/src/types.tsp

@@ -17,6 +17,19 @@ scalar ULID extends string;
 @maxLength(64)
 scalar Key extends string;
 
+/**
+ * ULID (Universally Unique Lexicographically Sortable Identifier).
+ * A key is a unique string that is used to identify a resource.
+ *
+ * TODO: this is a temporary solution to support both ULID and Key in the same spec for codegen.
+ */
+@pattern(
+  "^[a-z0-9]+(?:_[a-z0-9]+)*$|^[0-7][0-9A-HJKMNP-TV-Za-hjkmnp-tv-z]{25}$",
+)
+@minLength(1)
+@maxLength(64)
+scalar ULIDOrKey extends string;
+
 // NOTE (andras): key format enforcement isn't supported by TypeSpec (patternProperties). See: https://github.com/microsoft/typespec/discussions/1626
 /**
  * Set of key-value pairs.