Refactor code for consistency and enhanced functionality.

- Normalize path handling for buffer operations, supporting tilde expansion and absolute paths.
- Introduce `DisplayNameFor` to uniquely resolve buffer display names, minimizing filename clashes.
- Add new commands: `ShowWorkingDirectory` and `ChangeWorkingDirectory`.
- Refine keybindings and enhance existing commands for improved command flow.
- Adjust GUI and terminal renderers to display total line counts alongside filenames.
- Update coding style to align with project guidelines.

.junie/guidelines.md

@@ -1,39 +1,19 @@
 # Project Guidelines
 
 kte is Kyle's Text Editor — a simple, fast text editor written in C++17. It
-replaces the earlier C implementation, ke (see the ke manual in `ke.md`). The
+replaces the earlier C implementation, ke (see the ke manual in `docs/ke.md`). The
 design draws inspiration from Antirez' kilo, with keybindings rooted in the
 WordStar/VDE family and emacs. The spiritual parent is `mg(1)`.
 
 These guidelines summarize the goals, interfaces, key operations, and current
 development practices for kte.
 
-Style note: all code should be formatted with the current CLion C++ style.
-
 ## Goals
 
 - Keep the core small, fast, and understandable.
-- Provide an ncurses-based terminal-first editing experience, with an optional ImGui GUI.
+- Provide an ncurses-based terminal-first editing experience, with an additional ImGui GUI.
 - Preserve familiar keybindings from ke while modernizing the internals.
-- Favor simple data structures (e.g., gap buffer) and incremental evolution.
-
-## Interfaces
-
-- Command-line interface: the primary interface today.
-- GUI: planned ImGui-based interface.
-
-## Build and Run
-
-Prerequisites: a C++17 compiler, CMake, and ncurses development headers/libs.
-
-- macOS (Homebrew): `brew install ncurses`
-- Debian/Ubuntu: `sudo apt-get install libncurses5-dev libncursesw5-dev`
-
-- Configure and build (example):
-    - `cmake -S . -B cmake-build-debug -DCMAKE_BUILD_TYPE=Debug`
-    - `cmake --build cmake-build-debug`
-- Run:
-    - `./cmake-build-debug/kte [files]`
+- Favor simple data structures (e.g., piece table) and incremental evolution.
 
 Project entry point: `main.cpp`
 
@@ -52,31 +32,12 @@ Project entry point: `main.cpp`
 
 ## Keybindings (inherited from ke)
 
-kte aims to maintain ke’s command model while internals evolve. See `ke.md` for
-the full reference. Highlights:
-
-- K-command prefix: `C-k` enters k-command mode; exit with `ESC` or `C-g`.
-- Save/Exit: `C-k s` (save), `C-k x` or `C-k C-x` (save and exit), `C-k q` (quit
-  with confirm), `C-k C-q` (quit immediately).
-- Editing: `C-k d` (kill to EOL), `C-k C-d` (kill line), `C-k BACKSPACE` (kill
-  to BOL), `C-w` (kill region), `C-y` (yank), `C-u` (universal argument).
-- Navigation/Search: `C-s` (incremental find), `C-r` (regex search), `ESC f/b`
-  (word next/prev), `ESC BACKSPACE` (delete previous word).
-- Buffers/Files: `C-k e` (open), `C-k b`/`C-k p` (switch), `C-k c` (close),
-  `C-k C-r` (reload).
-- Misc: `C-l` (refresh), `C-g` (cancel), `C-k m` (run make), `C-k g` (goto line).
-
-Known behavior from ke retained for now:
-
-- Incremental search navigates results with arrow keys; search restarts from
-  the top on each invocation (known bug to be revisited).
+The file `docs/ke.md` contains the canonical reference for keybindings.
 
 ## Contributing/Development Notes
 
 - C++ standard: C++17.
-- Style: match existing file formatting and minimal-comment style.
-- Keep dependencies minimal; ImGui integration will be isolated behind a GUI
-  module.
+- Keep dependencies minimal.
 - Prefer small, focused changes that preserve ke’s UX unless explicitly changing
   behavior.