feature request: Knowledge base improvements

### Checks

- [x] I have searched [github.com/aws/amazon-q-developer-cli/issues](https://github.com/aws/amazon-q-developer-cli/issues?q=) and there are no duplicates of my issue
- [x] I have run `q doctor` in the affected terminal session
- [x] I have run `q restart` and replicated the issue again

### Operating system

Mac OS

### Expected behaviour

Current Limitations:
• No pagination controls (limit, offset, page number)
• No result count summary
• No metadata-only mode (file paths/names without content)
• Unclear result limits (appears capped at ~5 results)
• No control over snippet length

Suggested Enhancements:

High Relevance:
1. Add total result count in search response
1. Implement pagination parameters (limit, offset)
1. Add metadata-only mode to list matching file paths
1. Max results parameter - Let users specify how many results to return

Search refinements:
1. snippet_length - Control content preview size
1. include_content - Boolean to toggle full content vs metadata
1. sort_by - Sort results (relevance, date, name, path)
1. file_type - Filter by extension
1. date_range - Filter by modification date
1. fields - Specify which metadata fields to return

Advanced features:
1. export - Save results to file
1. count_only - Return just the count
1. distinct_files - Deduplicate by file path
1. context_lines - Control surrounding context (like grep -C)

### Actual behaviour

The tool is valuable for semantic search across large codebases, but these enhancements would make it much more practical and helps in moving away from having to host remote RAG solutions.

### Steps to reproduce

_No response_

### Environment

```yaml

```