feat(norms): hosts, containers and monitor response times are graded against their own normal (#5742)

Host CPU, memory and load per core, container CPU and memory, and every
monitor's response time learn a normal per hour (milestone 513, System 182).
A reading past its fixed cutoff but within its normal reads healthy and says
what is usual at this hour; one well out of it keeps its grade and is a
metric anomaly. Disk, a monitor down and an agent offline keep their cutoffs.

- Each normal's floor, the smallest departure that counts, is a setting:
  Settings -> Thresholds -> Normals (norms.floor.*). Defaults: host CPU 10
  points, host memory 5, load per core 10, container CPU 10 points of one
  core, container memory 5, monitor response 100 ms; Traefik's 2-point 4xx
  and 50 ms p95 floors move there from constants. learn_normal takes a
  floor function (floor_setting) read at each pass.
- learn_normal(parts=False): a host learns, its cores don't.
- Ingest records load_pct (load_1m / cores x 100), the figure pages grade.
- Shared grading: anomalies.against / graded, worst_reading(normals=),
  hosts' host_grades, docker usage(thresholds=, norms=), monitors'
  latency_grade. Applied to host vitals, the Hosts widget, MCP overview,
  Docker usage, and the monitor list, widget and page.
- The monitor and container pages list their anomalies.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

steward/core/formatting.py

@@ -233,16 +233,23 @@ def required(value: Any, what: str) -> Any:
 _SEVERITY = {"crit": 2, "warn": 1}
 
 
-def worst_reading(readings, thresholds: dict):
+def worst_reading(readings, thresholds: dict, normals: dict | None = None):
     """The reading furthest past its cutoff, as (label, value, grade), or None
     when every reading is within its cutoffs or missing.
 
     `readings` is (label, value, kind) triples, graded like status_class; the
     first of equally bad readings wins, so list them in the order a reader
-    should hear about them."""
+    should hear about them. `normals` ({kind: (Norm, floor)}) are the
+    resource's own normals for this hour: a reading past its cutoff but
+    within its normal is not past it (#5742)."""
+    from steward.core.anomalies import graded
+    normals = normals or {}
     worst, rank = None, 0
     for label, value, kind in readings:
-        grade = status_class(value, kind, thresholds)
+        if kind in normals:
+            grade = graded(value, kind, thresholds, *normals[kind], "%")[0]
+        else:
+            grade = status_class(value, kind, thresholds)
         if _SEVERITY.get(grade, 0) > rank:
             worst, rank = (label, value, grade), _SEVERITY[grade]
     return worst
@@ -327,6 +334,7 @@ METRICS: dict[str, tuple[str, str]] = {
     "load_1m": ("Load (1 min)", "runnable processes, averaged over a minute"),
     "load_5m": ("Load (5 min)", "runnable processes, averaged over 5 minutes"),
     "load_15m": ("Load (15 min)", "runnable processes, averaged over 15 minutes"),
+    "load_pct": ("Load per core", "1-minute load as a % of the host's cores; 100% keeps every core busy"),
     "uptime_secs": ("Uptime", "time since the host booted"),
     "seconds_since_seen": ("Time since the agent reported", "over 3 minutes means the agent is offline"),
     "clock_off_secs": ("Clock off by", "how far the host's clock is from Steward's, either way"),