docs: Update for decomposed repo structure

- AGENT-ONBOARDING: New repo map with daviestechlabs Gitea repos
- TECH-STACK: Reference handler-base instead of llm-workflows
- CODING-CONVENTIONS: Update project structure for new repos
- ADR 0006: Update GitRepository examples for Gitea repos

llm-workflows has been split into:
- handler-base, chat-handler, voice-assistant
- kuberay-images, argo, kubeflow, mlflow, gradio-ui

TECH-STACK.md

@@ -237,20 +237,26 @@
 
 ---
 
-## Python Dependencies (llm-workflows)
+## Python Dependencies (handler-base)
+
+Core library for all NATS handlers: [handler-base](https://git.daviestechlabs.io/daviestechlabs/handler-base)
 
 ```toml
 # Core
 nats-py>=2.7.0          # NATS client
 msgpack>=1.0.0          # Binary serialization
-aiohttp>=3.9.0          # HTTP client
+httpx>=0.27.0           # HTTP client
 
 # ML/AI
 pymilvus>=2.4.0         # Milvus client
-sentence-transformers   # Embeddings
 openai>=1.0.0           # vLLM OpenAI API
 
-# Kubeflow
+# Observability
+opentelemetry-api>=1.20.0
+opentelemetry-sdk>=1.20.0
+mlflow>=2.10.0          # Experiment tracking
+
+# Kubeflow (kubeflow repo)
 kfp>=2.12.1             # Pipeline SDK
 ```