Adds wp_ajax_prautoblogger_generate_image so images can be generated
for existing posts that were published before image gen was enabled
or fixed. Uses set_time_limit(120) to handle the Cloudflare API
latency that caused fatals when run via Code Snippets init hook.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Cron handlers (daily generation, metrics collection), AJAX handlers
(generate now, test connection), atomic generation lock, and model
registry access moved to PRAutoBlogger_Executor. Main orchestrator
retains hook registration, DB migrations, and cron schedule filter.
Backward-compatible proxy methods on PRAutoBlogger.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>