Add 5 skills from LFM + 12 skills total

New skills:
- blacknode-graph-workflow
- multi-agent-workflow-execution
- langgraph-agent-workflow
- langgraph-multi-agent-router
- three-tier-evaluation-pipeline

Config: LLM pipeline uses LFM on llama.cpp (8080)

skills/blacknode-graph-workflow/examples.md

@@ -0,0 +1,10 @@
+# Examples: blacknode-graph-workflow
+
+## Usage Example
+
+```python
+# How to use this skill
+# Inputs: Model configuration (NIM_MODEL, API keys for NVIDIA NIM, OpenAI, Anthropic), Node definitions with specified inputs and outputs (Literal, LLMAgent, FileWrite, etc.), Data sources (URLs, text content, or other inputs for the workflow)
+# Process: Initialize a blacknode.Graph instance to create the workflow structure → Add nodes to the graph with defined inputs and outputs (e.g., Literal, LLMAgent, FileWrite) → Define edges connecting nodes to establish data flow between them
+# Outputs: Processed results from the final node (e.g., printed text, written files, or generated data), Graph execution status and any errors encountered during execution
+```