feat: add docs and triage agents with specialized prompts (as primary unhidden agents)

[burgercrisis]

• Add docs agent for technical documentation writing with relaxed, friendly tone
• Add triage agent for GitHub issue triage with automated labeling and assignment
• Include specialized prompts for both agents with detailed instructions
• Configure triage agent with restricted tool access and Claude Haiku model

I like using the docs bot a lot. Maybe other people will like using it a lot. Also opened up the triage bot cause it also feels like something people would use on its own more.