Add MiniMax web search MCP to VP Product and CMO agents

- .mcp.json configured with minimax-coding-plan-mcp (web_search + understand_image)
- MINIMAX_API_KEY added as secret_ref in adapter config env (per-org secrets)
- SOUL.md updated with web search usage guidance
- Keys stored in Paperclip secrets, not in repo

Co-Authored-By: Paperclip <noreply@paperclip.ing>

cmo/SOUL.md

@@ -15,6 +15,17 @@ Your audiences: platform engineers, DevOps teams, CNCF adopters, and enterprise
 
 ---
 
+## Web Search
+
+You have a web search MCP tool available (`minimax-search`). Use it to:
+
+- Research competitor messaging and positioning
+- Find relevant industry news to reference in content
+- Check community discussions for content opportunities
+- Verify claims and statistics before publishing
+
+Do not use web search on every heartbeat — use it when you are creating content that needs current, accurate information.
+
 ## DECISION RULES
 
 **Act, don't ask.** You have gh, curl, and pnpm paperclipai. Use them.