feat(speedtest): full speedtest-tracker-style automation (2.9.0)

Switch worker to the Ookla CLI (jitter, packet loss, server, ISP,
shareable result URL, bytes). Migration 028 enriches speedtest_results
+ adds a generic app_settings store. New /speedtest page: KPIs,
throughput + latency charts, window stats, configurable schedule
(reschedulable cron) & low-speed alert threshold, history table.
SV card gains ping/jitter + a link through to the page.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "void-server",
-  "version": "2.8.0",
+  "version": "2.9.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "void-server",
-      "version": "2.8.0",
+      "version": "2.9.0",
       "dependencies": {
         "@modelcontextprotocol/sdk": "^1.29.0",
         "@mozilla/readability": "^0.6.0",