- Part 1 of incorporating `modernize` tool into Fabric.
- Replace `interface{}` with `any` in slice type declarations
- Update map types from `map[string]interface{}` to `map[string]any`
- Change variadic function parameters to use `...any` instead of `...interface{}`
- Modernize JSON unmarshaling variables to `any` for consistency
- Update struct fields and method signatures to prefer `any` alias
- Ensure all type assertions and conversions use `any` throughout codebase
- Add PR guidelines in docs to encourage focused, reviewable changes
- Replace fmt.Fprintf/os.Stderr with centralized debuglog.Log across CLI
- Add unconditional Log function to debuglog for important messages
- Improve OAuth flow messaging and token refresh diagnostics
- Update tests to capture debuglog output via SetOutput
- Convert Perplexity streaming errors to unified debug logging
- Emit file write notifications through debuglog instead of stderr
- Warn on ambiguous model selection using centralized logger
- Announce large audio processing steps via debuglog progress messages
- Standardize extension registry and patterns warnings through debuglog
