This commit adds the initial implementation of the `mmaitag` module,
a pluggable AI-based message classification processor.
The module supports two providers:
- `gemini`: uses the Gemini API via libcurl and JSON-C
- `gemini_mock`: a deterministic in-memory mock used for testing
Each log message is classified individually and tagged with a label
stored in a configurable message variable (default: `$.aitag`).
Included:
- Provider abstraction layer (`ai_provider.h`)
- Gemini provider with API key support (inline or via file)
- Prompt customization and input property selection
- Two regression tests: basic and invalid-key scenarios
- Sphinx documentation under `doc/configuration/modules`
Note: mmaitag is in its infancy and primarily a PoC. Future work
will improve batching, performance, and add more providers.
Refs:
- https://github.com/rsyslog/rsyslog/issues/5747 (AI-first strategy)
With the help of AI Agents: Codex, Gemini
