Refactor transcript fetching and processing scripts

- Introduced a new function `fetchTranscriptContent` to handle fetching transcripts with optional authentication.
- Enhanced error handling and logging for transcript fetching.
- Updated the `parseTranscriptToMessages` function to improve message parsing logic.
- Replaced the old session processing logic with a new approach that utilizes `SessionImport` records.
- Removed obsolete scripts related to manual triggers and whitespace fixing.
- Updated the server initialization to remove direct server handling, transitioning to a more modular approach.
- Improved overall code structure and readability across various scripts.

pages/api/dashboard/sessions.ts

@@ -150,7 +150,7 @@ export default async function handler(
       tokensEur: ps.tokensEur ?? undefined,
       initialMsg: ps.initialMsg ?? undefined,
       fullTranscriptUrl: ps.fullTranscriptUrl ?? null,
-      transcriptContent: ps.transcriptContent ?? null,
+      transcriptContent: null, // Transcript content is now fetched from fullTranscriptUrl when needed
     }));
 
     return res.status(200).json({ sessions, totalSessions });