Module text_buffer 

Split implementation of the Ropey-backed TextBuffer.

The goal of this submodule is to keep the TextBuffer implementation easy to navigate and extend by separating it into focused files:

• core.rs: struct definition + basic constructors/accessors
• lines.rs: line indexing helpers
• pos.rs: (line, col) conversions and cursor-ish movement
• slice.rs: extracting text
• edit.rs: mutation operations (insert/delete/apply edits)
• word.rs: word-ish motions (intentionally minimal, easy to swap later)

TextBuffer remains a single public type re-exported by buffer::mod.rs. All methods are inherent impls spread across these modules.

Structs

TextBuffer

A Ropey-backed text buffer.