Refresh puter UI, power telemetry and demand-aware monitoring

SAMPLING.md

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+# Sampling and events
+
+One cancellable scheduler follows `SamplingDemand`. No timer is scheduled while
+paused, or when the app has no visible window, menu-bar, alert, or recording consumer.
+Settings and startup pages do not request process inventory. Services are sampled
+only while their page is active. Background CPU/memory/network menu-bar readings
+use lightweight system counters, not process enumeration or per-app nettop.
+
+CPU time, I/O rates, fan speeds and service state still require samples: public
+macOS notifications are not a replacement for continuously changing counters.
+Recording deliberately retains system/process sampling in the background.
+App-history collection is opportunistic rather than an always-running daemon.
+
+Existing workspace notifications invalidate app and volume inventory; app-event
+bursts are coalesced over 200ms. Volume enumeration no longer runs every ten
+seconds. IOKit power-source, memory-pressure and thermal notifications remain.
+USB/port inventory still reconciles while hardware is being consumed, because
+the current implementation does not have an IOKit device-matching observer.
+
+Validation: eight SamplingDemand tests cover idle, pause, services, menu-bar,
+recording and alerts. The native sampler budget test passed: full process sample
+averaged 65.5ms versus 7.5ms for system-only telemetry on this machine. These are
+scan-cost measurements, not before/after whole-app CPU or energy measurements.
+
+## Profiling-driven corrections
+
+Demand now reads current application hidden state and the visibility, minimized
+state and occlusion of titled windows. A visible unfocused window remains live.
+Hide/unhide and window occlusion/minimize notifications reschedule the existing
+task; each scheduled wake also reconciles live demand before doing any work.
+There is no added visibility polling timer. Startup and explicit Refresh can
+request one inventory even without a visible consumer.
+
+Process groups are prepared once per inventory result, outside view evaluation.
+A bounded executable-path cache includes misses. Table rendering shares one
+sorted/filtered projection among category rows and the empty-state check; search
+still preserves matching-member behavior and group identity.
+
+Disk capacity is cached independently of disk activity: initial/manual refresh,
+volume enumeration, and at most once per minute on visible Performance. Normal
+telemetry samples reuse the cached capacity instead of querying the filesystem.
+See PROFILING.md for Release measurements and caveats.