feat(transit): add the TTC Toronto surface feed

TTC BusTime publishes keyless GTFS-Realtime VehiclePositions with real
coordinates for the surface network: ~1,180 buses and streetcars with
bearing and per-vehicle timestamps. Registering it is one registry row.

The subway is deliberately absent. BusTime covers surface vehicles only
and the subway publishes no positions, so Lines 1/2/4 are left out rather
than inferred from schedules — the same rule that keeps NYCT out.

Route numbers establish the mode: the three-digit 500-series is streetcar,
as are the four Blue Night routes on streetcar trackage. A leading 5 alone
would misclassify bus routes 50-59, so the rule is anchored and tested.

Licensing is the portal-wide Open Government Licence - Toronto; the CKAN
record for the BusTime NVAS dataset leaves its own licence field blank,
and the terms note says so rather than overstating the grant.

Refs #70

src/data/transitFeeds.js

@@ -115,6 +115,21 @@ function metroTransitRouteMode(routeId) {
   return 'bus';
 }
 
+/**
+ * TTC BusTime is the SURFACE feed: buses and streetcars, never the subway.
+ * Streetcar routes are the 500-series, plus the four Blue Night routes that
+ * run on streetcar trackage (301 Queen, 304 King, 306 Carlton, 310 Spadina);
+ * the rest of the 300-series is night buses.
+ * @param {string|null} routeId
+ * @returns {string}
+ */
+function ttcRouteMode(routeId) {
+  if (!routeId) return 'unknown';
+  if (/^5\d\d$/.test(routeId)) return 'tram';
+  if (/^(301|304|306|310)$/.test(routeId)) return 'tram';
+  return 'bus';
+}
+
 /**
  * Registry of feeds. Order is presentation order in the stats/credit text.
  * `loadRadiusKm` is the distance from `center` inside which the feed is polled.
@@ -270,6 +285,27 @@ export const TRANSIT_FEED_REGISTRY = Object.freeze([
     }),
     defaultMode: 'bus',
   }),
+  Object.freeze({
+    id: 'ttc-toronto',
+    name: 'TTC',
+    operator: 'Toronto Transit Commission',
+    region: 'Toronto, ON',
+    center: Object.freeze({ lat: 43.6532, lon: -79.3832 }),
+    loadRadiusKm: 45,
+    url: 'https://bustime.ttc.ca/gtfsrt/vehicles',
+    license: 'Open Government Licence \u2013 Toronto',
+    licenseUrl: 'https://open.toronto.ca/open-data-licence/',
+    attribution:
+      'Toronto Transit Commission \u2014 City of Toronto Open Data (Open Government Licence \u2013 Toronto)',
+    defaultEnabled: true,
+    terms: Object.freeze({
+      quote:
+        'The Information Provider grants you a worldwide, royalty-free, perpetual, non-exclusive licence to use the Information, including for commercial purposes ... Acknowledge the source of the Information by including any attribution statement specified by the Information Provider.',
+      note: 'The City publishes this endpoint from the TTC BusTime NVAS catalogue entry, whose own licence field reads \"License not specified\"; the quote above is the portal-wide Open Government Licence \u2013 Toronto the City applies to its open data, so the credit carries the licence name the way the Metro Transit entry carries its public-domain note. BusTime is the surface system: buses and streetcars report real positions, the subway reports none, so Lines 1/2/4 are simply absent rather than inferred. The endpoint sends no ETag or Last-Modified, so conditional requests fall through to the proxy snapshot TTL.',
+    }),
+    defaultMode: 'bus',
+    routeMode: ttcRouteMode,
+  }),
 ]);
 
 /**