Let admins block and unblock users

Add a moderation log to keep track of decisions as well.

Author: amCap1712

.idea/.gitignore

@@ -0,0 +1,20 @@
+BEGIN;
+
+ALTER TABLE "user" ADD COLUMN is_blocked BOOLEAN NOT NULL DEFAULT FALSE;
+CREATE TABLE moderation_log (
+    id                      INTEGER GENERATED BY DEFAULT AS IDENTITY,
+    user_id                 INTEGER NOT NULL,
+    moderator_id            INTEGER NOT NULL,
+    action                  moderation_action_type NOT NULL,
+    reason                  TEXT NOT NULL,
+    timestamp               TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW()
+);
+ALTER TABLE moderation_log ADD CONSTRAINT moderation_log_pkey PRIMARY KEY (id);
+ALTER TABLE moderation_log ADD CONSTRAINT moderation_log_user_id_fkey FOREIGN KEY (user_id) REFERENCES "user" (id);
+ALTER TABLE moderation_log ADD CONSTRAINT moderation_log_moderator_id_fkey FOREIGN KEY (moderator_id) REFERENCES "user" (id);
+CREATE INDEX moderation_log_user_id_idx ON moderation_log (user_id);
+
+ALTER TABLE "user" ADD COLUMN login_id UUID NOT NULL;
+CREATE UNIQUE INDEX user_login_id_idx ON "user" (login_id);
+
+COMMIT;