Refactor insights handling and error encoding in presentation layer

- Updated insights analyzer tests to use Utc for date handling.
- Added timezone support for insights retrieval, allowing insights to be bucketed by the user's local time.
- Introduced `encode_domain_error` for better error handling in API responses.
- Modified various handlers to utilize the new error encoding function.
- Enhanced insights API to reject unknown time zones and return appropriate errors.
- Updated frontend components to handle insights data with timezone awareness.
- Improved localization for insights sample counts.

crates/adapters/postgres/src/insights.rs

@@ -30,7 +30,7 @@ impl InsightsQuery for PostgresInsightsQuery {
                     to_char(watched_at AT TIME ZONE 'UTC', 'YYYY-MM-DD HH24:MI:SS') AS watched_at, \
                     watch_medium \
              FROM reviews \
-             WHERE user_id = $1 \
+             WHERE user_id = $1 AND remote_actor_url IS NULL \
              ORDER BY watched_at ASC",
         )
         .bind(user_id.value().to_string())