The SchedulerConfig struct and its persistence/API were unnecessary
indirection. Replace with a simple constant (reduced from 613s to 61s)
so the scheduler re-checks for detectable job types promptly after
going idle, improving the clean-install experience.
* pb: add job type max runtime setting
* plugin: default job type max runtime
* plugin: redesign scheduler loop
* admin ui: update scheduler settings
* plugin: fix scheduler loop state name
* plugin scheduler: restore backlog skip
* plugin scheduler: drop legacy detection helper
* admin api: require scheduler config body
* admin ui: preserve detection interval on save
* plugin scheduler: use job context and drain cancels
* plugin scheduler: respect detection intervals
* plugin scheduler: gate runs and drain queue
* ec test: reuse req/resp vars
* ec test: add scheduler debug logs
* Adjust scheduler idle sleep and initial run delay
* Clear pending job queue before scheduler runs
* Log next detection time in EC integration test
* Improve plugin scheduler debug logging in EC test
* Expose scheduler next detection time
* Log scheduler next detection time in EC test
* Wake scheduler on config or worker updates
* Expose scheduler sleep interval in UI
* Fix scheduler sleep save value selection
* Set scheduler idle sleep default to 613s
* Show scheduler next run time in plugin UI
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Co-authored-by: Copilot <copilot@github.com>
