fix(illness): keep chronic conditions out of rest mode

A chronic ongoing condition has no end date, so counting it as rest mode
kept the account in it for good: Day N counted from an onset years back,
cadence nudges never resumed and every streak gap since the onset was
bridged. Only active episodes that are not CHRONIC_ONGOING (acute,
recurring, flare) now trigger rest mode, and Day N counts from the
earliest of those. The achievements streak freeze applies the same
filter to its own episode query.

Chronic conditions stay context: a coincident vital deviation is still
framed as explained by any active episode, and the Coach block and the
briefing still name them, with restMode false.

Refs #1216

docs/api/openapi.yaml

@@ -75778,8 +75778,9 @@ components:
                 - day
               additionalProperties: false
             - type: "null"
-          description: "Rest Mode: present while an illness episode is active and the illness module is on, else null. Additive
-            since v1.40."
+          description: "Rest Mode: present while an illness episode that is not chronic ongoing (acute, recurring or flare) is
+            active and the illness module is on, else null. A chronic ongoing condition alone never sets it; `day`
+            counts from the earliest onset among the episodes that do. Additive since v1.40."
         line:
           type: string
           description: "Push / lock-screen line: cached-AI lead with a deterministic floor. Carries no number (no reading, dose or