Add a `CODEOWNERS` file

[jstirnaman]

Example:

# .github/CODEOWNERS

# Default owner for everything
* @your-docs-team

# Product-specific ownership
/content/influxdb/cloud/         @cloud-docs-owner
/content/influxdb/clustered/     @clustered-docs-owner
/content/telegraf/               @telegraf-docs-owner
/api-docs/                       @api-docs-owner

# Infra/tooling
/.circleci/                      @docs-infra
/layouts/                        @docs-infra

Aadd these lines for agent clarity:

# Agent-modified files - require human review
AGENTS.md                        @docs-lead
CLAUDE.md                        @docs-lead

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Validation: After merging, open a test PR touching one of those paths—GitHub should auto-request the right reviewer.