v1.3.0 - Switch basemap to OpenFreeMap vector tiles

Why

• CARTO now watermarks keyless raster tiles with "API KEY REQUIRED" (since late Aug 2026). Every client embed using the dark theme is affected, e.g. https://www.3saints.ca/where-to-buy.
• The light theme was pulling tiles directly from openstreetmap.org, which the OSM tile usage policy forbids for widgets distributed to third-party sites.

What

• Both themes now use OpenFreeMap vector tiles (Positron light, Dark dark) rendered by MapLibre GL 5.24.0 through @maplibre/maplibre-gl-leaflet 0.1.4. No API key, no request limits, free for commercial use.
• Leaflet markers, popups and marker clustering are untouched. Theme toggle calls setStyle on the same WebGL context.
• Keyless Esri Light/Dark Gray canvas raster tiles are used only if WebGL or the MapLibre scripts are unavailable.
• Mandatory "OpenFreeMap © OpenMapTiles Data from OpenStreetMap" attribution is shown in the Leaflet attribution control, with links.
• Fixes a race: when the API response arrived before the map dependencies finished loading, addMarkers crashed on this.map being null. loadStores now parks the data and the init path replays it.
• Version bumped to 1.3.0 in the header, README CDN links and demo snippet. Tag 1.3.0 after merge so cdn.jsdelivr.net/gh/voyera/weedcrawler_map@1.3.0/cannabis-store-map.min.js resolves; clients then bump the version in their script tag.

Verified locally

• Demo API key: 2481 stores fetched, 1451 Ontario markers clustered, light → dark → light toggles, no console errors.
• Dark style fully applied after toggle (background rgb(12,12,12), 282 rendered basemap features).