chore: add package description for JSR score

jsr.json had no description field, costing the 'Has a description' point on
the JSR score. Add one and match package.json to it.

jsr.json

@@ -1,6 +1,7 @@
 {
   "name": "@buddy/leaflet-components",
   "version": "0.1.1",
+  "description": "Leaflet.js as native Web Components — one custom element per Leaflet object.",
   "license": "MIT",
   "exports": {
     ".": "./src/index.ts",

package.json

@@ -1,7 +1,7 @@
 {
   "name": "leaflet-web-components",
   "version": "0.1.1",
-  "description": "LeafletJS as Web Components",
+  "description": "Leaflet.js as native Web Components — one custom element per Leaflet object.",
   "main": "dist/index.npm.js",
   "module": "dist/index.npm.js",
   "types": "dist/index.npm.d.ts",