feat(Telemetry): Emit CLI usage events from an API middleware - #8541

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Changes

Closes #8319

Flagsmith CLI requests currently don't emit dedicated usage telemetry. This adds middleware to record authenticated CLI usage so it can be observed consistently without introducing database or cache reads in the telemetry path.

• Emits cli.request.made for authenticated CLI requests.
• Captures CLI version, OS, architecture, organisation, request status, and user identity where applicable.
• Supports both authenticated users and Master API Keys.
• Shares organisation resolution logic with the existing MCP telemetry middleware.

Review effort: 2/5

How did you test this code?

Added unit tests covering authenticated and unauthenticated requests, Master API Keys, error responses, CLI version passthrough, non-CLI User-Agents, and zero database queries during CLI telemetry handling.

Also verified with:

make test opts='tests/unit/telemetry/test_unit_telemetry_middleware.py -n0'
make lint
make typecheck
git diff --check