Add Publisher v2 + 5 extracted skills

Publisher fixes:
- Checkout new branch before push (was pushing main ref)
- Verify files staged before commit
- Handle duplicate files gracefully
- Clean error reporting per stage

Skills merged to main:
- mcp-server-setup (from pipeshub-ai)
- research-pipeline (from Blacknode)
- multi-agent-sequential-workflow (from Fast-LLM-Agent-MCP)
- unifai-workflow-execution (from UnifAI)
- code-review-agent-workflow (from AgentKit)

skills/mcp-server-setup/examples.md

@@ -0,0 +1,10 @@
+# Examples: mcp-server-setup
+
+## Usage Example
+
+```python
+# How to use this skill
+# Inputs: MCP server configuration details, PipesHub credentials
+# Process: Step 1: Clone the `pipeshub-ai/mcp-server` repository using `git clone https://github.com/pipeshub-ai/mcp-server.git` → Step 2: Navigate to the cloned directory with `cd mcp-server` → Step 3: Run the interactive installer by executing `./install.sh`
+# Outputs: Running MCP server, .env file generated
+```