Clarify skills messages in list() and search()

Update error messages to better explain how to enable skills, and return
empty list if skills are disabled.

When OI tries to list skills, it shows them, but then it can't actually
call them and it gets very confused.

(cherry picked from commit 64e42567f1426fd1224673f9c8440bc7eec2ec4e)

Author: endolith

interpreter/core/computer/skills/skills.py

@@ -24,6 +24,9 @@ class Skills:
     """
     Manages access to pre-imported automation skills.
 
+    Note: Skills system must be enabled via profile (like 'the01') or by creating
+    OpenInterpreter with import_skills=True.
+
     Available methods:
     - list(): Returns names of available skills
     - search(query): Lists available skills (currently same as list())
@@ -47,6 +50,15 @@ def list(self):
         Returns:
             list[str]: Names of available skills with () to indicate they're callable
         """
+        if not self.computer.import_skills:
+            print("Skills are disabled. To enable skills, either use a profile like 'the01' that supports skills, "
+                  "or create an instance of OpenInterpreter with import_skills=True")
+            return []
+
+        if not self.computer._has_imported_skills:
+            print("Skills have not been imported yet.")
+            return []
+
         return [
             file.replace(".py", "()")
             for file in os.listdir(self.path)
@@ -70,6 +82,15 @@ def search(self, query):
         Returns:
             list[str]: Names of available skills with () to indicate they're callable
         """
+        if not self.computer.import_skills:
+            print("Skills are disabled. To enable skills, either use a profile like 'the01' that supports skills, "
+                  "or create an instance of OpenInterpreter with import_skills=True")
+            return []
+
+        if not self.computer._has_imported_skills:
+            print("Skills have not been imported yet.")
+            return []
+
         return [
             file.replace(".py", "()")
             for file in os.listdir(self.path)
@@ -84,6 +105,9 @@ def import_skills(self):
         This method is called automatically during system setup to load available skills.
         Assistant should use list(), search(), or call skills directly instead of this method.
         """
+        if not self.computer.import_skills:
+            return
+
         previous_save_skills_setting = self.computer.save_skills
 
         self.computer.save_skills = False