KNELPerf v2 wave 1: Ultix scheduler breakout + loop skeleton + reports (#826)

- scheduler/: day/night engine (conf-driven redesign), psi/perfsnap collectors,
  proxmox-ctl, systemd timer templates — ported from ~/projects/ultix per the
  breakout map in scheduler/README.md
- loop/: perf-loop driver (baseline/audit/tweak/rebaseline), cpu-bench (new CPU
  leg), baseline-diff (tolerance compare) — smoke-tested locally
- docs/ARCHITECTURE.md: full program design (loop, resource groups, VM/spindle
  balancing, k8s-vs-Slurm, beszel+RAPL/iDRAC telemetry spine, workload classes,
  solar/HA + two-site power economics)
- docs/report-amt-power-telemetry.md + docs/report-moonlight-desktop.md

Redmine: https://projects.knownelement.com/issues/826#note-2

scheduler/daynight/knelperf-daynight.conf.example

@@ -0,0 +1,28 @@
+# /etc/knelperf/daynight.conf — knelperf-daynight.sh configuration.
+# Copy to /etc/knelperf/daynight.conf and edit per host. Every field is
+# optional; omit slices/sections you do not manage on this host.
+#
+# Slice spec format (space-separated list):
+#   slice[:CPUWeight[:AllowedCPUs[:MemoryHigh]]]
+# Empty field = skip that property. Day AND night lists are required for
+# any slice you list (reboot-safety invariant: day values == unit-file
+# defaults).
+
+# Example (workstation, 8 vCPU — mirrors the ultix values):
+# DAY_SLICES="reachableceo-batch.slice:25:0-5:12G reachableceo-gateway.slice:900::"
+# NIGHT_SLICES="reachableceo-batch.slice:400:0-6:30G reachableceo-gateway.slice:500::"
+
+# Example (PVE host with a batch pool):
+# DAY_SLICES="knelperf-batch.slice:25:0-3:8G"
+# NIGHT_SLICES="knelperf-batch.slice:400:0-7:24G"
+
+# Block devices for night readahead boost (partitions auto-included):
+# BLOCK_DEVS="/dev/sdb"
+
+# Defaults shown in the script; override only what differs:
+# DATA_RA_DAY=256
+# DATA_RA_NIGHT=2048
+# DIRTY_DAY=1073741824
+# DIRTY_NIGHT=2147483648
+# DIRTY_BG_DAY=268435456
+# DIRTY_BG_NIGHT=536870912