feat: add email verification & password reset link

server/relay-server/migrations/003_email_verification.sql

@@ -0,0 +1,12 @@
+ALTER TABLE users ADD COLUMN IF NOT EXISTS email_verified BOOLEAN NOT NULL DEFAULT FALSE;
+
+CREATE TABLE IF NOT EXISTS email_tokens (
+    id         BIGSERIAL PRIMARY KEY,
+    user_id    BIGINT NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    token      TEXT NOT NULL UNIQUE,
+    kind       TEXT NOT NULL,
+    expires_at BIGINT NOT NULL,
+    created_at BIGINT NOT NULL
+);
+
+CREATE INDEX IF NOT EXISTS idx_email_tokens_token ON email_tokens(token);