zlog: Fall back to printing module path instead of *unknown* or just crate name (#29691)

Closes #ISSUE

Release Notes:

- N/A *or* Added/Fixed/Improved ...

crates/zlog/src/zlog.rs

@@ -61,6 +61,8 @@ impl log::Log for Zlog {
             scope: module_scope,
             level,
             message: record.args(),
+            // PERF(batching): store non-static paths in a cache + leak them and pass static str here
+            module_path: record.module_path().or(record.file()),
         });
     }
 
@@ -80,6 +82,7 @@ macro_rules! log {
                 scope: logger.scope,
                 level,
                 message: &format_args!($($arg)+),
+                module_path: Some(module_path!()),
             });
         }
     }
@@ -267,6 +270,7 @@ impl log::Log for Logger {
             scope: self.scope,
             level,
             message: record.args(),
+            module_path: record.module_path(),
         });
     }