release: bump version to v0.7.0

Updates package.json and artifacthub-pkg.yml for the v0.7.0 release.
Includes all changes since v0.6.0:
- RBAC fix for Polaris dashboard proxy access (PR #22)
- Settings test selector fix (PR #22)
- Package name correction from solaris to polaris (PR #26)
- E2E preflight check (PR #24)
- Missing test dependencies (PR #28)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "headlamp-polaris",
-  "version": "0.6.0",
+  "version": "0.7.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "headlamp-polaris",
-      "version": "0.6.0",
+      "version": "0.7.0",
       "license": "Apache-2.0",
       "devDependencies": {
         "@kinvolk/headlamp-plugin": "^0.13.0",