- Add "Processing X files..." indicator in chat while handling attachments
- Indicator transitions to "Analyzing X files..." for large files needing LLM summarization
- Reuse streaming message for seamless transition to LLM response
- Add FileAnalyzer service for large file summarization with 10s timeout
- Skip analysis for borderline files (within 20% of 8K threshold)
- Read up to 50KB from original file for analysis (not just truncated content)
- Remove base64 blobs from JSON before analysis to reduce prompt size
- Add AttachmentDisplay component for showing file badges on messages
- Persist attachments to IndexedDB with message references
- Add chat state methods: setStreamContent, removeMessage
- Clean up debug logging