feat: rename skills and remove obsolete skill optimizer files

Author: hotlong

skills/objectstack-automation/SKILL.md

@@ -1,5 +1,5 @@
 ---
-name: automation-design
+name: objectstack-automation
 description: >
   Design ObjectStack automation (Flows, Workflows, Triggers, Approvals).
   Use when building visual logic flows, state machines, scheduled jobs,

skills/objectstack-ui/SKILL.md

@@ -1,5 +1,5 @@
 ---
-name: ui-design
+name: objectstack-ui
 description: >
   Design ObjectStack user interfaces (Views, Apps, Dashboards, Reports, Actions).
   Use when creating list views, form layouts, navigation structures, dashboard