Perplexity AI provider
Added full setup flow with live API‑key validation.
Supports sonar-* and any other Perplexity chat‑completion models.
New service constants: perplexity_api_key, perplexity_model.
New endpoint: https://api.perplexity.ai/chat/completions.
🔧** Improvements**
Coordinator refactor
Removed duplicate code, centralised helper logic, and tightened error handling.
Prompt construction and entity sampling unchanged, but runtime memory footprint is slightly lower.
All functional migration constants (CONFIG_VERSION, config‑flow VERSION) remain unchanged.
🛠️ Developer notes
No breaking changes to existing providers, service parameters, or YAML automations.
If you maintain local forks, you only need to merge:
New constants in const.py.
validate_perplexity() and async_step_perplexity() in config_flow.py.
process_with_perplexity() handler plus dispatch entry in coordinator.py.
Happy automating!