fix: Remove invalid pattern properties from showtime workflows

- Remove unsupported `pattern` property from workflow_dispatch inputs
- Add one-time push trigger to showtime-cleanup.yml for workflow registration
- Runtime validation still handled in bash steps

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

.github/workflows/showtime-cleanup.yml

@@ -2,6 +2,11 @@ name: 🎪 Showtime Cleanup
 
 # Scheduled cleanup of expired environments
 on:
+  # One-time push trigger to register the workflow
+  push:
+    paths:
+      - '.github/workflows/showtime-cleanup.yml'
+
   schedule:
     - cron: '0 */6 * * *'  # Every 6 hours
 
@@ -13,7 +18,6 @@ on:
         required: false
         default: '48'
         type: string
-        pattern: '^[0-9]+$'
 
 # Common environment variables
 env:

.github/workflows/showtime-trigger.yml

@@ -16,7 +16,6 @@ on:
         description: 'Specific SHA to deploy (optional, defaults to latest)'
         required: false
         type: string
-        pattern: '^[a-f0-9]{40}$'
 
 # Common environment variables for all jobs
 env: