Merge origin/main into feat/external-2fa-codes. Resolve formatting
conflicts caused by biome rollout; preserve both feature streams:
PR's external 2FA token + signing-session 2FA proof additions plus
main's RateLimit/RecipientExpired/signingReminders/date-auto-insert.
In complete-document-with-token.ts, drop the duplicate early
field-fetching block introduced when main moved that logic later
with date auto-insert support; keep the EXTERNAL_TWO_FACTOR_AUTH
check using derivedRecipientActionAuth.
Introduces the ability for users with the **Assistant** role to prefill
fields on behalf of other signers. Assistants can fill in various field
types such as text, checkboxes, dates, and more, streamlining the
document preparation process before it reaches the final signers.
ephraimduncan
Lucas Smith
David Nguyen
Ephraim Duncan