chore add core rust project files and diesel migrations

Track required workspace crates, scripts, and historical diesel migrations so the repository contains the complete runnable backend baseline.

Made-with: Cursor

htyws_models/migrations/2022-05-20-113811_add_comments_tbl/down.sql

@@ -0,0 +1 @@
+-- This file should undo anything in `up.sql`

htyws_models/migrations/2022-05-20-113811_add_comments_tbl/up.sql

@@ -0,0 +1,19 @@
+-- Your SQL goes here
+
+create table comments
+(
+    id           varchar   not null
+        constraint comments_pk
+            primary key,
+    ref_id       varchar   not null,
+    ref_type     varchar   not null,
+    parent_id    varchar,
+    created_at   timestamp not null,
+    created_by   varchar   not null,
+    creator_name varchar,
+    content      jsonb
+);
+
+create unique index comments_id_uindex
+    on comments (id);
+