Document current coding-workflow stack state

Snapshot of where opencode + Qwen3-Coder + MCPs + Kimi-Linear + voice
  + Phoenix tracing land today, plus in-flight (oc-tree, kimi-linear
  context ramp) and next (ComfyUI) items with pointers to per-project
  NEXT_STEPS.md guides.

gitea-opencode-agent-project/agents/documentation-agent.sh

@@ -0,0 +1,26 @@
+# Documentation Agent
+
+## Overview
+This agent specializes in generating and maintaining documentation using the qwen3-coder model (30b) for the homelab infrastructure project.
+
+## Capabilities
+- Generates documentation from code analysis
+- Creates standardized documentation templates
+- Updates documentation based on infrastructure changes
+- Analyzes documentation gaps and suggests improvements
+
+## Usage
+```bash
+# Generate documentation with qwen3-coder
+qwen3-coder --generate-docs \
+  --model "qwen3-coder:30b" \
+  --project "homelab-infrastructure" \
+  --output "docs/homelab.md"
+```
+
+## Integration
+This agent integrates with:
+- Code repositories
+- Network diagrams
+- Configuration files
+- Deployment scripts