fix(robot): resolve relative library paths in namespace cache validation

Namespace cache validation failed for files importing libraries via
relative paths (e.g. ../../resources/libraries/common.py), causing
unnecessary full rebuilds on every warm start.

Two issues fixed:
- validate_namespace_meta now passes the source file's directory as
  base_dir when falling back to get_library_meta/get_variables_meta,
  so relative paths resolve correctly
- get_library_meta and get_variables_meta initialize import_name
  before the try block to avoid UnboundLocalError when find_library
  or find_variables fails

Author: d-biehl

packages/robot/src/robotcode/robot/diagnostics/imports_manager.py

@@ -821,13 +821,14 @@ def validate_namespace_meta(self, meta: NamespaceMetaData) -> bool:
             return False
 
         # Level 2: dependency checks — direct comparison, no hashing
+        base_dir = os.path.dirname(meta.source)
         for key, saved_value in meta.dependency_fingerprints.items():
             if key.startswith("lib:"):
                 lib_name = key[4:]
                 try:
                     lib_meta = self.get_cached_library_meta(lib_name)
                     if lib_meta is None:
-                        lib_meta, _, _ = self.get_library_meta(lib_name)
+                        lib_meta, _, _ = self.get_library_meta(lib_name, base_dir=base_dir)
                     if lib_meta is None or lib_meta != saved_value:
                         return False
                 except (SystemExit, KeyboardInterrupt):
@@ -851,7 +852,7 @@ def validate_namespace_meta(self, meta: NamespaceMetaData) -> bool:
                 try:
                     var_meta = self.get_cached_variables_meta(var_name)
                     if var_meta is None:
-                        var_meta, _ = self.get_variables_meta(var_name)
+                        var_meta, _ = self.get_variables_meta(var_name, base_dir=base_dir)
                     if var_meta is None or var_meta != saved_value:
                         return False
                 except (SystemExit, KeyboardInterrupt):
@@ -1204,6 +1205,7 @@ def get_library_meta(
         base_dir: str = ".",
         variables: Optional[Dict[str, Optional[Any]]] = None,
     ) -> Tuple[Optional[LibraryMetaData], str, bool]:
+        import_name = name
         ignore_arguments = False
         try:
             import_name = self.find_library(name, base_dir=base_dir, variables=variables)
@@ -1278,6 +1280,7 @@ def get_variables_meta(
         resolve_variables: bool = True,
         resolve_command_line_vars: bool = True,
     ) -> Tuple[Optional[LibraryMetaData], str]:
+        import_name = name
         try:
             import_name = self.find_variables(
                 name,