Fix agent commands with proper content structure

- Added disable-model-invocation flag to agent commands
- Added proper task template with {{USER_MESSAGE}}
- Added detailed instructions for each command
- Updated dexto-code, dexto-database, dexto-github, dexto-pdf
- Updated prometheus-bug, prometheus-feature

This should fix "Unknown skill" errors when using these commands.

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

commands/prometheus-bug.md

@@ -1,8 +1,9 @@
 ---
-description: "Analyze and reproduce bugs using Prometheus bug analyzer agent with context retrieval and reproduction steps"
+description: "Prometheus Bug Analyzer - Bug analysis and reproduction"
+disable-model-invocation: true
 ---
 
-Invoke the Prometheus Bug Analyzer to investigate and reproduce the reported bug.
+Use Prometheus Bug Analyzer to investigate and fix bugs.
 
 **Task:**
 {{USER_MESSAGE}}