Rewrite srdwm in Rust: working X11 and Wayland backends, Lua config

The C++ prototype (moved to legacy-cpp/) was mostly a design skeleton:
X11 and Windows backends were partially real, Wayland created the
wlroots object graph but never wired a single event listener, macOS
was stub except monitor enumeration, and the Lua engine's srd.bind()
stored a key-combo string but never the actual closure. See
docs/PRIOR_ART.md for the full audit.

This replaces it with a Cargo workspace:

- srdwm-core: platform-independent window/workspace/monitor state,
  a real master-stack tiling layout, and SmartPlacement grid/cascade/
  snap-to-edge placement - fixing several bugs in the C++ version
  (hardcoded 2-column grid, cascade that never cascaded, snap-to-edge
  that always returned a fixed rect). 35 unit tests.
- srdwm-config: the srd Lua API via mlua, implementing the surface
  docs/DEFAULTS.md always documented but the C++ engine never actually
  built (srd.window.close()/focus(direction), srd.workspace.next(),
  real keybinding closures, require("srd") support). 10 unit tests.
- srdwm-x11: a real reparenting WM with a drawn title bar (buttons,
  drag, resize), verified live under Xephyr - frame placement and
  client offset match srdwm-core's computed geometry exactly, and the
  decoration renders correctly on screen.
- srdwm-wayland: a from-scratch smithay compositor (the C++ version
  had nothing working to port from) - runs via the winit backend,
  tracks xdg-shell toplevels through the same WindowManager and
  hit-testing code X11 uses, verified to start/render/run without
  crashing. Decorations are solid-color (no text yet); see
  docs/IMPLEMENTATION_STATUS.md for exact scope.
- srdwm-windows / srdwm-macos: structured, cfg-gated designs informed
  by komorebi/glazewm and yabai/AeroSpace respectively (see
  docs/PRIOR_ART.md), honestly marked as unbuilt/unverified since this
  sandbox has no Windows or macOS target.

1 files changed, 0 insertions, 227 deletions

diff --git a/src/platform/wayland_platform.h b/src/platform/wayland_platform.h
deleted file mode 100644
index 3df5867..0000000
--- a/src/platform/wayland_platform.h
+++ /dev/null
@@ -1,227 +0,0 @@
-#ifndef SRDWM_WAYLAND_PLATFORM_H
-#define SRDWM_WAYLAND_PLATFORM_H
-
-#include "platform.h"
-#ifndef USE_WAYLAND_STUB
-#include <wayland-server-core.h>
-#endif
-// Forward-declare Wayland and wlroots types to avoid version-specific headers.
-struct wl_display; struct wl_registry; struct wl_compositor; struct wl_shm; struct wl_seat; struct wl_output; struct wl_shell; struct wl_listener; struct wl_surface;
-struct wlr_backend; struct wlr_renderer; struct wlr_compositor; struct wlr_output_layout; struct wlr_cursor; struct wlr_xcursor_manager; struct wlr_seat;
-struct wlr_xdg_shell; struct wlr_xdg_surface; struct wlr_xdg_toplevel;
-struct wlr_output; struct wlr_pointer_motion_event; struct wlr_pointer_button_event; struct wlr_pointer_axis_event; struct wlr_keyboard_key_event;
-struct wlr_xdg_decoration_manager_v1;
-#include <map>
-#include <memory>
-#include <vector>
-
-// Forward declarations
-class SRDWindow;
-class Monitor;
-
-// Wayland-specific platform implementation
-class WaylandPlatform : public Platform {
-public:
-    WaylandPlatform();
-    ~WaylandPlatform();
-
-    // Platform interface implementation
-    bool initialize() override;
-    void shutdown() override;
-    
-    // Event handling
-    bool poll_events(std::vector<Event>& events) override;
-    void process_event(const Event& event) override;
-
-    // SRDWindow management
-    std::unique_ptr<SRDWindow> create_window(const std::string& title, int x, int y, int width, int height) override;
-    void destroy_window(SRDWindow* window) override;
-    void set_window_position(SRDWindow* window, int x, int y) override;
-    void set_window_size(SRDWindow* window, int width, int height) override;
-    void set_window_title(SRDWindow* window, const std::string& title) override;
-    void focus_window(SRDWindow* window) override;
-    void minimize_window(SRDWindow* window) override;
-    void maximize_window(SRDWindow* window) override;
-    void close_window(SRDWindow* window) override;
-
-    // Monitor management
-    std::vector<Monitor> get_monitors() override;
-    Monitor get_primary_monitor() override;
-
-    // Input handling
-    void grab_keyboard() override;
-    void ungrab_keyboard() override;
-    void grab_pointer() override;
-    void ungrab_pointer() override;
-
-    // Utility
-    // SRDWindow decorations (Wayland implementation)
-    void set_window_decorations(SRDWindow* window, bool enabled) override;
-    void set_window_border_color(SRDWindow* window, int r, int g, int b) override;
-    void set_window_border_width(SRDWindow* window, int width) override;
-    bool get_window_decorations(SRDWindow* window) const override;
-
-    std::string get_platform_name() const override { return "Wayland"; }
-    bool is_wayland() const override { return true; }
-    bool is_x11() const override { return false; }
-    bool is_windows() const override { return false; }
-    bool is_macos() const override { return false; }
-
-private:
-    static WaylandPlatform* instance_;
-    // Wayland-specific members
-    struct wl_display* display_;
-    struct wl_registry* registry_;
-    struct wl_compositor* compositor_;
-    struct wl_shm* shm_;
-    struct wl_seat* seat_;
-    struct wl_output* output_;
-    struct wl_shell* shell_;
-    
-    // wlroots backend
-    struct wlr_backend* backend_;
-    struct wlr_renderer* renderer_;
-    struct wlr_compositor* wlr_compositor_;
-    struct wlr_output_layout* output_layout_;
-    struct wlr_cursor* cursor_;
-    struct wlr_xcursor_manager* xcursor_manager_;
-    struct wlr_seat* wlr_seat_;
-    
-    // Shell protocols
-    struct wlr_xdg_shell* xdg_shell_;
-    // struct wlr_layer_shell_v1* layer_shell_;
-    
-    // XWayland support (temporarily disabled)
-    // struct wlr_xwayland* xwayland_;
-    // struct wlr_xwayland_server* xwayland_server_;
-    
-    // SRDWindow tracking
-    std::map<struct wlr_surface*, SRDWindow*> surface_window_map_;
-    std::map<struct wlr_xdg_surface*, SRDWindow*> xdg_window_map_;
-    // std::map<struct wlr_xwayland_surface*, SRDWindow*> xwayland_window_map_;
-    
-    // Monitor information
-    std::vector<Monitor> monitors_;
-    Monitor primary_monitor_;
-    
-    // Event handling
-    bool event_loop_running_;
-    std::vector<Event> pending_events_;
-    
-    // Private methods
-    bool setup_wlroots_backend();
-    bool setup_compositor();
-    bool setup_shell_protocols();
-    // bool setup_xwayland();
-    
-    // Event handling
-    void handle_registry_global(struct wl_registry* registry, uint32_t name, 
-                               const char* interface, uint32_t version);
-    void handle_registry_global_remove(struct wl_registry* registry, uint32_t name);
-    
-    // Shell protocol handlers
-    void handle_xdg_surface_new(struct wlr_xdg_surface* surface);
-    void handle_xdg_surface_destroy(struct wlr_xdg_surface* surface);
-    void handle_xdg_toplevel_new(struct wlr_xdg_toplevel* toplevel);
-    void handle_xdg_toplevel_destroy(struct wlr_xdg_toplevel* toplevel);
-    
-    // XWayland handlers (temporarily disabled)
-    // void handle_xwayland_surface_new(struct wlr_xwayland_surface* surface);
-    // void handle_xwayland_surface_destroy(struct wlr_xwayland_surface* surface);
-    
-    // Output handlers
-    void handle_output_new(struct wlr_output* output);
-    void handle_output_destroy(struct wlr_output* output);
-    void handle_output_frame(struct wlr_output* output);
-    
-    // Input handlers
-    void handle_pointer_motion(struct wlr_pointer_motion_event* event);
-    void handle_pointer_button(struct wlr_pointer_button_event* event);
-    void handle_pointer_axis(struct wlr_pointer_axis_event* event);
-    void handle_keyboard_key(struct wlr_keyboard_key_event* event);
-    
-    // SRDWindow management helpers
-    SRDWindow* find_window_by_surface(struct wlr_surface* surface);
-    SRDWindow* find_window_by_xdg_surface(struct wlr_xdg_surface* surface);
-    // SRDWindow* find_window_by_xwayland_surface(struct wlr_xwayland_surface* surface);
-    void manage_xdg_window(struct wlr_xdg_surface* surface);
-    // void manage_xwayland_window(struct wlr_xwayland_surface* surface);
-    void unmanage_window(SRDWindow* window);
-    
-    // Monitor helpers
-    void update_monitor_info();
-    void handle_output_mode(struct wlr_output* output);
-    void handle_output_scale(struct wlr_output* output);
-    
-    // Input helpers
-    void setup_keyboard_grab();
-    void setup_pointer_grab();
-    void handle_key_event(uint32_t key, bool pressed);
-    void handle_button_event(uint32_t button, bool pressed);
-    
-    // Utility helpers
-    void create_surface_window(struct wlr_surface* surface);
-    void destroy_surface_window(struct wlr_surface* surface);
-    void update_surface_window(struct wlr_surface* surface);
-    
-    // Event conversion
-    void convert_wlroots_event_to_srdwm_event(void* event_data, EventType type);
-    
-    // Error handling
-    void handle_wlroots_error(const std::string& error);
-    
-    // Decoration methods
-    void setup_decoration_manager();
-    void handle_decoration_request(struct wlr_xdg_surface* surface, uint32_t mode);
-    
-    // Static callback functions
-    static void registry_global_handler(void* data, struct wl_registry* registry,
-                                       uint32_t name, const char* interface, uint32_t version);
-    static void registry_global_remove_handler(void* data, struct wl_registry* registry, uint32_t name);
-    
-    static void xdg_surface_new_handler(struct wl_listener* listener, void* data);
-    static void xdg_surface_destroy_handler(struct wl_listener* listener, void* data);
-    static void xdg_toplevel_new_handler(struct wl_listener* listener, void* data);
-    static void xdg_toplevel_destroy_handler(struct wl_listener* listener, void* data);
-    
-    // static void xwayland_surface_new_handler(struct wl_listener* listener, void* data);
-    // static void xwayland_surface_destroy_handler(struct wl_listener* listener, void* data);
-    
-    static void output_new_handler(struct wl_listener* listener, void* data);
-    static void output_destroy_handler(struct wl_listener* listener, void* data);
-    static void output_frame_handler(struct wl_listener* listener, void* data);
-    
-    static void pointer_motion_handler(struct wl_listener* listener, void* data);
-    static void pointer_button_handler(struct wl_listener* listener, void* data);
-    static void pointer_axis_handler(struct wl_listener* listener, void* data);
-    static void keyboard_key_handler(struct wl_listener* listener, void* data);
-    
-    // Event listeners removed in stubbed build to avoid wl_listener dependency
-    // wlroots event listeners (instantiated only in real Wayland path)
-    #ifndef USE_WAYLAND_STUB
-    struct wl_listener xdg_surface_new_listener_;
-    struct wl_listener xdg_surface_destroy_listener_;
-    struct wl_listener xdg_toplevel_new_listener_;
-    struct wl_listener xdg_toplevel_destroy_listener_;
-    struct wl_listener output_new_listener_;
-    struct wl_listener output_destroy_listener_;
-    struct wl_listener output_frame_listener_;
-    struct wl_listener pointer_motion_listener_;
-    struct wl_listener pointer_button_listener_;
-    struct wl_listener pointer_axis_listener_;
-    struct wl_listener keyboard_key_listener_;
-    #endif
-
-    // Decoration state
-    bool decorations_enabled_;
-    struct wlr_xdg_decoration_manager_v1* decoration_manager_;
-    
-    // struct wl_listener xwayland_new_surface;
-    // struct wl_listener xwayland_destroy;
-    
-    // Additional listeners removed in stubbed build
-};
-
-#endif // SRDWM_WAYLAND_PLATFORM_H
-
-