chore: squash migrations

server/crates/arbiter-server/migrations/2026-02-14-171124-0000_init/up.sql

@@ -46,6 +46,7 @@ create table if not exists useragent_client (
     id integer not null primary key,
     nonce integer not null default(1), -- used for auth challenge
     public_key blob not null,
+    key_type integer not null default(1), -- 1=Ed25519, 2=ECDSA(secp256k1)
     created_at integer not null default(unixepoch ('now')),
     updated_at integer not null default(unixepoch ('now'))
 ) STRICT;

server/crates/arbiter-server/migrations/2026-03-13-000000_add_key_type/down.sql

@@ -1,2 +0,0 @@
--- Not reversible without data loss; drop the column to revert
-ALTER TABLE useragent_client DROP COLUMN key_type;

server/crates/arbiter-server/migrations/2026-03-13-000000_add_key_type/up.sql

@@ -1 +0,0 @@
-ALTER TABLE useragent_client ADD COLUMN key_type INTEGER NOT NULL DEFAULT 1;