[Add] Proper User managment

migrations/009_user_invitations.sql

@@ -0,0 +1,29 @@
+CREATE TABLE user_invitations (
+    invitation_id CHAR(36) NOT NULL,
+    token_hash BINARY(32) NOT NULL,
+    iota_id BIGINT NOT NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    expires_at TIMESTAMP NULL,
+    state ENUM('pending', 'redeemed', 'revoked', 'expired') NOT NULL DEFAULT 'pending',
+    redeemed_user_id BIGINT NULL,
+    redeemed_at TIMESTAMP NULL,
+    revoked_at TIMESTAMP NULL,
+    PRIMARY KEY (invitation_id),
+    KEY idx_user_invitations_target_state (iota_id, state),
+    CONSTRAINT fk_user_invitations_iota
+        FOREIGN KEY (iota_id) REFERENCES iotas(id) ON DELETE CASCADE
+);
+
+CREATE TABLE pending_iota_user_provisioning (
+    user_id BIGINT NOT NULL,
+    iota_id BIGINT NOT NULL,
+    invitation_id CHAR(36) NOT NULL,
+    username VARBINARY(255) NOT NULL,
+    public_key BLOB NOT NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    PRIMARY KEY (user_id, iota_id),
+    CONSTRAINT fk_pending_iota_user_provisioning_iota
+        FOREIGN KEY (iota_id) REFERENCES iotas(id) ON DELETE CASCADE,
+    CONSTRAINT fk_pending_iota_user_provisioning_invitation
+        FOREIGN KEY (invitation_id) REFERENCES user_invitations(invitation_id) ON DELETE CASCADE
+);