Inputs are now just ATPROTO_HANDLE, ATPROTO_APP_PASSWORD, REMANSO_API
(or matching --handle, --app-password, --api). The script resolves the
handle to a DID via public.api.bsky.app, then resolves the DID to a
PDS via plc.directory — same path the server's verifier uses. Works
for any AT Protocol PDS (Bluesky, eurosky, self-hosted) without the
caller having to know the PDS URL.
Wraps the createSession + Authorization: Bearer flow so callers don't
need to assemble curl by hand. Reads BSKY_IDENTIFIER / BSKY_PASSWORD /
BSKY_PDS / REMANSO_API from env (or matching flags). Defaults to
bsky.social so non-bsky-hosted accounts must set BSKY_PDS explicitly,
e.g. BSKY_PDS=https://eurosky.social.