Text: Reflow module is convoluted and should be refactored / replaced

[joshka]

Problem

The wrapping in reflow is fairly convoluted, which makes it difficult to maintain (fix problems and add new features). This caused a problem in #193

https://github.com/tui-rs-revival/ratatui/blob/492af7a92d264a590ebbf4eb90b45657e30dfd30/src/widgets/reflow.rs#L55-L209

Solution / Constraints

• Simplify the wrapping logic
• Move the wrapping logic to the right place (perhaps under the text module?)
• Implement the wrapping against a single Line to avoid having nested iterators
• Allow the wrapping logic to be used in any widget, not just paragraph
• Maintain backwards compatibility (allow graceful deprecation of the current methods rather than breaking all current code)
• Spec this out before implementation (because implementing this without a spec leads to very long and painful PRs)