docs: move the changelog entry to changelog.d

changelog.d/945-cctv-vegvesen-kartverket-heights.md

@@ -0,0 +1,14 @@
+- Give each Statens vegvesen camera its own ground height from Kartverket's
+  keyless point-height API (CC BY 4.0) instead of one flat 150 m prior, so
+  mountain-pass cameras no longer sit hundreds of metres below the terrain
+  where neither the point-height prior nor the ground snap resolves. About 850
+  of ~855 cameras get a height; the rest keep the old prior. Requests carry 20
+  points, the most the API answers from its 1 m terrain model, eight at a time
+  (~6 s cold). Cameras over water use the water surface rather than the
+  sea-floor depth the API returns there; for bridge cameras that is still
+  below the deck. Heights are cached for good and misses for 6 h, so a refresh
+  only asks about new or moved cameras. After a 429, a 5xx or a network
+  failure the lookup stops and backs off (Retry-After, else 10 min). The lane
+  waits at most 12 s from its start; a slower lookup fills the cache for the
+  next refresh. `CCTV_VEGVESEN_HEIGHTS=0` turns it off. Follow-up to #929
+  (trygvehhh, #945).