merge by name and social urls (#2027)

* Remove speakers missing from Sched

* Sync more socials

* Track duplicate speakers

* Actually use the equality sets

* Collect sessions from previous years even if the username is different

* Don't show data from the future

* Fix 0s in old UI (was it always like this?)

Author: hasparus

scripts/sync-sched/count-speakers-without-details.ts

@@ -16,7 +16,7 @@ import type { SchedSpeaker } from "@/app/conf/_api/sched-types"
     console.log("Reading speakers.json...")
 
     const speakersData = await readFile(speakersFilePath, "utf-8")
-    const speakers: SchedSpeaker[] = JSON.parse(speakersData)
+    const speakers: SchedSpeaker[] = JSON.parse(speakersData).speakers
 
     const speakersWithoutDetails = speakers.filter(
       speaker => !speaker["~syncedDetailsAt"],