partykit: preserve slow document hydration

[spencerc99]

Summary

• give Supabase document hydration one shared 15-second deadline instead of aborting each read at 5 seconds
• record slow and retried hydration timing without logging document data
• add real loopback regression coverage for a response that arrives after 5 seconds

Rationale

Production telemetry showed document reads repeatedly hitting the previous 5-second cutoff even when Supabase could still return the room. A shared deadline preserves explicit-error retries while allowing a slow viable read to complete.

This keeps @supabase/supabase-js; it does not change the database client or dependencies.

Testing

• bun test partykit/__tests__ (289 passed)
• bun run check:partykit
• Wrangler production Worker dry-run bundle
• git diff --check origin/main...HEAD

No changeset, public docs, starter-template update, or screenshots are needed because this changes only internal PartyKit persistence timing and telemetry.

[pkg-pr-new]

Open in StackBlitz

bun add https://pkg.pr.new/@playhtml/common@438

bun add https://pkg.pr.new/playhtml@438

bun add https://pkg.pr.new/@playhtml/react@438

commit: 151289b