Refactor blog module and remove blog-related functionality

- Removed blog router and associated API endpoints.
- Deleted blog persistence functions and related query parameters.
- Removed blog schemas and models from the codebase.
- Introduced common crate for shared types, including DateTimeWithTimeZoneWrapper.
- Added Thought and Follow models with corresponding migrations.
- Updated dependencies in Cargo.toml files to reflect changes.
- Adjusted tests to remove references to the blog module.

thoughts-backend/.env

@@ -1,6 +1,6 @@
 HOST=0.0.0.0
 PORT=8000
 #DATABASE_URL="sqlite://dev.db"
-# DATABASE_URL="postgresql://postgres:postgres@localhost/thoughts"
-DATABASE_URL=postgres://thoughts_user:postgres@database:5432/thoughts_db
+DATABASE_URL="postgresql://postgres:postgres@localhost/thoughts"
+#DATABASE_URL=postgres://thoughts_user:postgres@database:5432/thoughts_db
 PREFORK=1