v0.3.0 — ktunneld: per-user tokens, subdomain ownership, dashboard

The relay is now a service. ktunneld plugs into frps and issues personal tokens (hashed at rest, shown once, revocable one by one), enforces subdomain ownership and per-user limits, and serves an admin dashboard with an audit log. There is no shared frps secret any more.

Users

ktunnel login kt1.…     # the token carries the relay address and domain
ktunnel http 3000

Administrators

ktunneld user add alice
ktunneld token issue alice --label laptop
ktunneld reserve api alice
ktunneld ls / kill / token revoke

Revoke, disable and kill take effect at the next heartbeat (≤30 s); ktunnel exits with the reason instead of silently retrying. See server/README.md for deployment. Verify downloads against SHA256SUMS.

Full Changelog: v0.2.0...v0.3.0