feat: add invite code validity controls

- Add invite code starts/expires fields across contracts, API, Spacetime bindings, and admin UI
- Enforce pending/expired invite code redemption behavior and expose admin status
- Add admin write-operation confirmation guard and documentation
- Add invite code contract/runtime tests

server-rs/crates/spacetime-client/src/module_bindings/profile_invite_code_type.rs

@@ -12,6 +12,8 @@ pub struct ProfileInviteCode {
     pub metadata_json: String,
     pub created_at: __sdk::Timestamp,
     pub updated_at: __sdk::Timestamp,
+    pub starts_at: Option<__sdk::Timestamp>,
+    pub expires_at: Option<__sdk::Timestamp>,
 }
 
 impl __sdk::InModule for ProfileInviteCode {
@@ -27,6 +29,8 @@ pub struct ProfileInviteCodeCols {
     pub metadata_json: __sdk::__query_builder::Col<ProfileInviteCode, String>,
     pub created_at: __sdk::__query_builder::Col<ProfileInviteCode, __sdk::Timestamp>,
     pub updated_at: __sdk::__query_builder::Col<ProfileInviteCode, __sdk::Timestamp>,
+    pub starts_at: __sdk::__query_builder::Col<ProfileInviteCode, Option<__sdk::Timestamp>>,
+    pub expires_at: __sdk::__query_builder::Col<ProfileInviteCode, Option<__sdk::Timestamp>>,
 }
 
 impl __sdk::__query_builder::HasCols for ProfileInviteCode {
@@ -38,6 +42,8 @@ impl __sdk::__query_builder::HasCols for ProfileInviteCode {
             metadata_json: __sdk::__query_builder::Col::new(table_name, "metadata_json"),
             created_at: __sdk::__query_builder::Col::new(table_name, "created_at"),
             updated_at: __sdk::__query_builder::Col::new(table_name, "updated_at"),
+            starts_at: __sdk::__query_builder::Col::new(table_name, "starts_at"),
+            expires_at: __sdk::__query_builder::Col::new(table_name, "expires_at"),
         }
     }
 }

server-rs/crates/spacetime-client/src/module_bindings/runtime_profile_invite_code_admin_upsert_input_type.rs

@@ -10,6 +10,8 @@ pub struct RuntimeProfileInviteCodeAdminUpsertInput {
     pub admin_user_id: String,
     pub invite_code: String,
     pub metadata_json: String,
+    pub starts_at_micros: Option<i64>,
+    pub expires_at_micros: Option<i64>,
     pub updated_at_micros: i64,
 }
 

server-rs/crates/spacetime-client/src/module_bindings/runtime_profile_invite_code_snapshot_type.rs

@@ -10,6 +10,8 @@ pub struct RuntimeProfileInviteCodeSnapshot {
     pub user_id: String,
     pub invite_code: String,
     pub metadata_json: String,
+    pub starts_at_micros: Option<i64>,
+    pub expires_at_micros: Option<i64>,
     pub created_at_micros: i64,
     pub updated_at_micros: i64,
 }