fix: restore libwayland redox.patch to working state, update docs

- Reverted redox.patch to original 39-line version (build-tested)
- Documented libwayland→qtbase→kded6 build dependency chain
- Updated WAYLAND-IMPLEMENTATION-PLAN.md to v2.1
- Deleted 45 stale .bak patch files
- pkgar restored from packages/ backup

local/docs/WAYLAND-IMPLEMENTATION-PLAN.md

@@ -1,5 +1,5 @@
 # Red Bear OS Wayland Implementation Plan
-**Version:** 2.0 (2026-05-06)
+**Version:** 2.1 (2026-05-06)
 **Status:** Canonical Wayland subsystem plan — **Wayland-only path, no framebuffer workarounds**
 
 ## Architecture Decision (2026-05-06)
@@ -154,3 +154,22 @@ Hardware DRM/KMS rendering depends on `redox-drm` driver maturity.
 
 Success criterion: `redbear-compositor: client 65536 connected` followed by
 `redbear-compositor: dispatch` (not a page fault).
+
+### Build Dependency Chain (Critical, discovered 2026-05-06)
+
+When modifying libwayland source or `local/patches/libwayland/redox.patch`, the
+full chain must be rebuilt:
+
+```
+libwayland recipe → repo/x86_64-unknown-redox/libwayland.pkgar
+qtbase recipe     → copies pkgar into sysroot → links Qt6 Wayland QPA
+kf6-kded6 recipe  → links against qtbase/sysroot/libwayland-client.a
+```
+
+**Failure mode**: Modifying only libwayland does NOT update qtbase's static copy
+of `libwayland-client.a`. The old binary persists in qtbase's sysroot. All
+three recipes must be force-rebuilt (delete `target/` directories) AND the
+repo pkgar cache must be regenerated.
+
+**Recovery**: If `repo/x86_64-unknown-redox/libwayland.pkgar` is deleted, a
+backup exists at `packages/x86_64-unknown-redox/libwayland.pkgar`.

local/patches/libwayland/redox.patch

@@ -36,31 +36,4 @@
 +}
  #include <sys/file.h>
  #include <sys/stat.h>
-+--- a/src/wayland-client.c
-++++ b/src/wayland-client.c
-+@@ -649,6 +649,11 @@
-+ wl_proxy_add_listener(struct wl_proxy *proxy,
-+ 		      void (**implementation)(void), void *data)
-+ {
-++	if (!proxy) {
-++		fprintf(stderr, "FATAL: wl_proxy_add_listener(NULL) caller=%p -- returning error\n",
-++		        __builtin_return_address(0));
-++		return -1;
-++	}
-+ 	if (proxy->flags & WL_PROXY_FLAG_WRAPPER)
-+ 		wl_abort("Proxy %p is a wrapper\n", proxy);
-+ 
-+@@ -2448,6 +2453,7 @@
-+ wl_proxy_get_version(struct wl_proxy *proxy)
-+ {
-++	if (!proxy) return 0;
-+ 	return proxy->version;
-+ }
-+ 
-+@@ -2566,6 +2572,7 @@
-+ wl_proxy_get_display(struct wl_proxy *proxy)
-+ {
-++	if (!proxy) return NULL;
-+ 	return proxy->display;
-+ }
-  
+