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/migration/src/lib.rs

@@ -1,7 +1,7 @@
 pub use sea_orm_migration::prelude::*;
 
 mod m20240101_000001_init;
-mod m20240816_160144_blog;
+mod m20250905_000001_init;
 
 pub struct Migrator;
 
@@ -10,7 +10,7 @@ impl MigratorTrait for Migrator {
     fn migrations() -> Vec<Box<dyn MigrationTrait>> {
         vec![
             Box::new(m20240101_000001_init::Migration),
-            Box::new(m20240816_160144_blog::Migration),
+            Box::new(m20250905_000001_init::Migration),
         ]
     }
 }