Add road type color mode to route visualization

Extract highway=* tags from BRouter tiledesc messages alongside surface
data and add a new "Road Type" color mode that colors the route polyline
and elevation chart by OSM highway classification (cycleway, residential,
path, etc.). Includes color palette, legend, hover labels, i18n (EN+DE),
unit tests for tag extraction, and E2E tests.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/i18n/src/locales/de.ts

@@ -102,6 +102,7 @@ export default {
       elevation: "Höhe",
       surface: "Untergrund",
       grade: "Steigung",
+      highway: "Straßentyp",
       surfaceLegend: "Farbe nach Straßenbelag",
       surfaceUnavailable: "Untergrunddaten für dieses Profil nicht verfügbar",
     },
@@ -111,6 +112,7 @@ export default {
       loss: "Höhenmeter abwärts",
       profile: "Höhenprofil",
       grade: "Steigungsprofil",
+      highway: "Straßentypenprofil",
       low: "Tief",
       high: "Hoch",
     },

packages/i18n/src/locales/en.ts

@@ -102,6 +102,7 @@ export default {
       elevation: "Elevation",
       surface: "Surface",
       grade: "Grade",
+      highway: "Road Type",
       surfaceLegend: "Color by road surface type",
       surfaceUnavailable: "Surface data not available for this profile",
     },
@@ -111,6 +112,7 @@ export default {
       loss: "Elevation Loss",
       profile: "Elevation Profile",
       grade: "Grade Profile",
+      highway: "Road Type Profile",
       low: "Low",
       high: "High",
     },