docs(server-macros): fix typo in AUTH_METADATA_CONST doc comment

OpenShell is one word; reference name in the doc should be
OPENSHELL_AUTH_METADATA, not OPEN_SHELL_AUTH_METADATA.

Addresses review nit on PR #1596.

Signed-off-by: Mrunal Patel <mrunalp@gmail.com>

Author: mrunalp

crates/openshell-server-macros/src/lib.rs

@@ -200,7 +200,7 @@ fn snake_to_pascal(ident: &str) -> String {
 /// service module is what disambiguates between services — every impl
 /// lives in its own module (`crate::grpc::AUTH_METADATA`,
 /// `crate::inference::AUTH_METADATA`), so a fixed name reads more
-/// naturally than `OPEN_SHELL_AUTH_METADATA` / `INFERENCE_AUTH_METADATA`.
+/// naturally than `OPENSHELL_AUTH_METADATA` / `INFERENCE_AUTH_METADATA`.
 const AUTH_METADATA_CONST: &str = "AUTH_METADATA";
 
 fn trait_ident(item: &ItemImpl) -> Result<Ident> {