Evaluate approach for existing find file page (/-/find_file/) after in-page search implementation
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## Background
Following the implementation of in-page file search in #430775, we need to determine the best approach for handling the existing find file page at `/-/find_file/`.
## Proposal
As suggested by @derekferguson in #430775, the safest approach would be to:
1. **Redirect the existing page** (`/-/find_file/`) to the repository page with the file search automatically opened
2. **Monitor usage** after the redirect is implemented to understand:
- How many visits the URL still receives
- Whether people have bookmarked the direct URL
- If there are external links pointing to this page
## Implementation Steps
1. Implement redirect from `/-/find_file/` to repository page with search opened
2. Add analytics/monitoring to track:
- Number of redirects from the old URL
- User behavior after redirect
3. Based on data collected, decide whether it's safe to completely remove the page
## Success Criteria
- [ ] Redirect is implemented and working correctly
- [ ] Analytics are in place to monitor usage
- [ ] Data collection period completed (suggest 1-2 release cycles)
- [ ] Decision made on permanent removal based on usage data
## Related Issues
- #430775 - Allow for find file search to be on the page (parent issue)
- #22426 - Context-aware file search (next iteration)
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