Add skill definitions (SKILL.md + run.py) for all agent tools

skills/save_memory/SKILL.md

@@ -0,0 +1,13 @@
+---
+name: save_memory
+description: Save something important to your persistent memory. Use this to remember facts about users, lessons learned, project context, or anything you want to recall in future conversations. Memories survive restarts.
+parameters:
+  topic:
+    type: string
+    description: "Short topic name for the memory file (e.g. 'user_prefs', 'project_x', 'lessons')"
+    required: true
+  content:
+    type: string
+    description: The memory content to save
+    required: true
+---