v1.2.0

Migrate the API gateway to the AI Tutor API v1.

• Base URL is now https://stage.ai-tutor.ai/api/v1 (includes the /api/v1 prefix); override via the lumination_core_api_base_url filter.
• The API is asynchronous: request() submits a job and polls until it completes. New submit() and poll() methods allow browser-driven polling for long-running jobs (summaries, quizzes).
• Auth header switched to x-api-key; expanded HTTP error mapping.

Extensions require this version (Core 1.2.0+).

v1.1.1

• Add tool title heading level setting (H1/H2) in Appearance tab
• Fix readme.txt stable tag mismatch

v1.1.0

Add Tool Text Color picker in Appearance tab for dark theme compatibility.

v1.0.0

Initial release - Lumination Core shared infrastructure plugin.