[Feat]: Expose chart annotation read and write via Netdata MCP

Problem

The Netdata cloud MCP server does not expose chart annotations.

Description

Chart annotations are a useful way of marking charts to indicate things like infrastructure changes or deployments. As such, they would be extremely useful in an AI enhanced workflow.

Consider:

An issue is raised (via netdata or externally) and the engineer goes to work. Tracing back issues in charts is good but the troubleshooting process will likely involve multiple steps of changes (some will hopefully help resolve the issue and some may make it worse, or neither). The ability to tag a chart during your troubleshooting workflow so that you can keep track of the effect of each change would be extremely useful. Useful in general, but especially useful in an AI assisted workflow where we could configure our agent to always make a chart annotation for each step/phase of our change. Rapid iteration is often challenging because of exactly the ability to know what effect the changes had.

Likewise, annotations could be added at stages of a deployment or rollout to track changes overall and changes between roll-out phases.

Hopefully this type of write operation is relatively low-risk because of the thing that it is changing.

Importance

really want

Value proposition

It will likely make AI/MCP enabled workflows more effective while at the same time providing human-visible indicators of environmental/configurational changes.

Proposed implementation

No response