* perf(monitor): improve monitor query and chart performance for large ranges
- enable LTTB sampling in the shared line chart to bound rendered points
- empty io/network in monitor search now means no name filter, returning
all device rows in one query instead of fanning out per device
- merge device names recorded in the monitor db into io/network/gpu
options so removed devices stay selectable; move logic to service layer
- add composite indexes (name, created_at) on monitor_ios/monitor_networks
and (product_name, created_at) on monitor_gpus
- stop migrating the unused MonitorGPU model into MonitorDB
- fix the memory param which was compared against "mem" and never matched
* chore(monitor): remove monitor test fixtures
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Co-authored-by: ssongliu <sloooop1x@gmail.com>