Round every heading readout through one shared helper

The transit, ALPR, vessel, CCTV and flight/military context fixes each
wrapped 359.5° to north with an inline Math.round(x) % 360. They now call
roundHeadingDegrees in src/data/headingDegrees.js, which also wraps negative
and multi-turn bearings. normalizeHeading moves there with it, and
cockpitMath re-exports it so existing imports keep working. It now adds a
turn only to a negative remainder, so a bearing just under half a degree
keeps its precision.

The awareness, Local ADS-B, cockpit wind, cockpit heading and Street Level
readouts use the same helper. The Cockpit's TRACK ACQUIRED signal rounded
without wrapping and could read COURSE 360°; it now uses
formatHeadingReadout, which shows --- for a track that is not finite.

scripts/format-scope.json

@@ -1180,5 +1180,6 @@
   "src/testSupport/hudReadouts.mjs",
   "src/ui/stores/firstRun.js",
   "src/firstRunLauncherView.test.mjs",
-  "src/firstRunCopy.js"
+  "src/firstRunCopy.js",
+  "src/data/headingDegrees.test.mjs"
 ]

scripts/package-boundaries.json

@@ -745,6 +745,7 @@
   "cctv-controls": {
     "exports": ["./ui/cctv"],
     "modules": [
+      "src/data/headingDegrees.js",
       "src/ui/cctv.js",
       "src/ui/cctvBindings.js",
       "src/ui/cctvCalibration.js",
@@ -814,6 +815,7 @@
       "./ui/cockpit/vision"
     ],
     "modules": [
+      "src/data/headingDegrees.js",
       "src/ui/cockpit.js",
       "src/ui/cockpitBriefing.js",
       "src/ui/cockpitBriefPages.js",
@@ -883,6 +885,7 @@
   "ui-shell": {
     "exports": ["./ui/shell"],
     "modules": [
+      "src/data/headingDegrees.js",
       "src/i18n/marker.js",
       "src/ui/mobileShell.js",
       "src/exclusiveSurfaces.js",
@@ -1253,6 +1256,7 @@
   "civil-flights": {
     "exports": ["./layers/flights"],
     "modules": [
+      "src/data/headingDegrees.js",
       "src/i18n/marker.js",
       "src/cyberSonar.js",
       "src/data/aircraftClass.js",
@@ -1315,6 +1319,7 @@
   "military-flights": {
     "exports": ["./layers/military"],
     "modules": [
+      "src/data/headingDegrees.js",
       "src/i18n/marker.js",
       "src/cyberSonar.js",
       "src/data/aircraftClass.js",
@@ -1400,6 +1405,7 @@
   "vessel-layer": {
     "exports": ["./layers/vessels"],
     "modules": [
+      "src/data/headingDegrees.js",
       "src/layers/vessels/cards.js",
       "src/layers/vessels/evidence.js",
       "src/layers/vessels/index.js",
@@ -1645,6 +1651,7 @@
   "awareness-layer": {
     "exports": ["./layers/awareness"],
     "modules": [
+      "src/data/headingDegrees.js",
       "src/i18n/marker.js",
       "src/cyberSonar.js",
       "src/cockpitMath.js",
@@ -1783,6 +1790,7 @@
   "cctv-layer": {
     "exports": ["./layers/cctv"],
     "modules": [
+      "src/data/headingDegrees.js",
       "src/data/cctvCards.js",
       "src/data/cctvGizmo.js",
       "src/data/cctvLod.js",
@@ -1911,6 +1919,7 @@
   "alpr-cameras": {
     "exports": ["./layers/alpr"],
     "modules": [
+      "src/data/headingDegrees.js",
       "src/layers/alpr/index.js",
       "src/layers/alpr/model.js",
       "src/layers/alpr/policy.js",
@@ -2189,6 +2198,7 @@
       "./standalone/catalog"
     ],
     "modules": [
+      "src/data/headingDegrees.js",
       "src/ui/placeNames.js",
       "src/cyberSonarScene.js",
       "src/cyberSonar.js",
@@ -3163,6 +3173,7 @@
   "application-layer-construction": {
     "exports": ["./application/layers"],
     "modules": [
+      "src/data/headingDegrees.js",
       "src/cyberSonar.js",
       "src/data/approxDistance.js",
       "src/data/bhoteKoshiEvent.js",
@@ -4319,6 +4330,7 @@
   "transit-standalone": {
     "exports": ["./layers/transit/standalone"],
     "modules": [
+      "src/data/headingDegrees.js",
       "src/cyberSonar.js",
       "src/celestialRing.js",
       "src/data/approxDistance.js",
@@ -4396,6 +4408,7 @@
   "transit-layer": {
     "exports": ["./layers/transit"],
     "modules": [
+      "src/data/headingDegrees.js",
       "src/data/iconOrientation.js",
       "src/data/inputOwnership.js",
       "src/data/transitFeeds.js",
@@ -4623,6 +4636,7 @@
   "tools": {
     "exports": ["./tools"],
     "modules": [
+      "src/data/headingDegrees.js",
       "src/tools/index.js",
       "src/tools/catalog.js",
       "src/tools/schema.js",