cub: full AUR package manager + Phase 1-5 native build tools

cub redesign (local/recipes/system/cub/):
- AUR RPC v5 client (serde_json) with search/info
- ~/.cub/ user-local recipe/source/repo storage
- Enhanced PKGBUILD parser: optdepends, .SRCINFO, split packages, 19 linuxism patterns
- Recipe generation: host: prefix on dev-deps, shallow_clone, cargopath, installs, optional-packages
- Dependency resolver: scans build errors for missing commands/headers/libs/pkgconfig, maps to packages
- Dependency installation: checks installed packages, fetches AUR deps, interactive prompt
- ~110 Arc→Redox dependency mappings
- ratatui TUI: search, info, install, build, query views
- 14 Arch-style CLI switches (-S/-Si/-Syu/-G/-R/-Q/-Qi/-Ql)
- 65 tests, 0 failures, clean build

Phase 1-5 native build tools (local/recipes/dev/):
- P1 Substrate: tar, m4, diffutils (gnulib bypass), mkfifo kernel patch (1085 lines)
- P2 Build Systems: bison, flex, meson (standalone wrapper), ninja-build, libtool
- P3 Native GCC: gcc-native, binutils-native (cross-compiled for redox host)
- P4 Native LLVM: llvm-native (clang + lld from monorepo)
- P5 Native Rust: rust-native (rustc + cargo)
- Groups: build-essential-native, dev-essential expanded

Config:
- redbear-mini: +7 tools (diffutils, tar, bison, flex, meson, ninja, m4)
- redbear-full: +4 native tools (gcc, binutils, llvm, rust)
- All recipes moved to local/ with symlinks for cookbook discovery (Red Bear policy)

Docs:
- BUILD-TOOLS-PORTING-PLAN.md: phased porting roadmap
- CUB-WORKFLOW-ASSESSMENT.md: gap analysis and integration assessment

recipes/tools/diffutils

@@ -0,0 +1 @@
+../../local/recipes/tools/diffutils

recipes/tools/diffutils/diffutils.patch

@@ -1,88 +0,0 @@
-diff -ruw source/lib/cmpbuf.c source-new/lib/cmpbuf.c
---- source/lib/cmpbuf.c	2017-01-01 04:22:36.000000000 -0700
-+++ source-new/lib/cmpbuf.c	2018-12-29 07:31:43.920193561 -0700
-@@ -71,8 +71,8 @@
- 	     ancient AIX hosts that set errno to EINTR after uncaught
- 	     SIGCONT.  See <news:1r77ojINN85n@ftp.UU.NET>
- 	     (1993-04-22).  */
--	  if (! SA_RESTART && errno == EINTR)
--	    continue;
-+	  //if (! SA_RESTART && errno == EINTR)
-+	  //  continue;
- 
- 	  return SIZE_MAX;
- 	}
-diff -ruw source/lib/getdtablesize.c source-new/lib/getdtablesize.c
---- source/lib/getdtablesize.c	2017-05-18 10:23:32.000000000 -0600
-+++ source-new/lib/getdtablesize.c	2018-12-29 07:32:31.709586573 -0700
-@@ -109,6 +109,7 @@
- int
- getdtablesize (void)
- {
-+#if !defined(__redox__)
-   struct rlimit lim;
- 
-   if (getrlimit (RLIMIT_NOFILE, &lim) == 0
-@@ -117,6 +118,7 @@
-       && lim.rlim_cur != RLIM_SAVED_CUR
-       && lim.rlim_cur != RLIM_SAVED_MAX)
-     return lim.rlim_cur;
-+#endif
- 
-   return INT_MAX;
- }
-diff -ruw source/lib/getprogname.c source-new/lib/getprogname.c
---- source/lib/getprogname.c	2017-01-31 11:36:50.000000000 -0700
-+++ source-new/lib/getprogname.c	2018-12-29 07:34:15.432575388 -0700
-@@ -51,6 +51,14 @@
- # include <sys/procfs.h>
- #endif
- 
-+#if defined(__redox__)
-+# include <string.h>
-+# include <unistd.h>
-+# include <stdio.h>
-+# include <fcntl.h>
-+# include <limits.h>
-+#endif
-+
- #include "dirname.h"
- 
- #ifndef HAVE_GETPROGNAME             /* not Mac OS X, FreeBSD, NetBSD, OpenBSD >= 5.4, Cygwin */
-@@ -177,6 +185,17 @@
-         }
-     }
-   return NULL;
-+# elif defined(__redox__)
-+  char filename[PATH_MAX];
-+  int fd = open ("sys:exe", O_RDONLY);
-+  if (fd > 0) {
-+    int len = read(fd, filename, PATH_MAX-1);
-+    if (len > 0) {
-+       filename[len] = '\0';
-+       return strdup(filename);
-+    }
-+  }
-+  return NULL;
- # else
- #  error "getprogname module not ported to this OS"
- # endif
-diff -ruw source/lib/sigprocmask.c source-new/lib/sigprocmask.c
---- source/lib/sigprocmask.c	2017-05-18 10:23:32.000000000 -0600
-+++ source-new/lib/sigprocmask.c	2018-12-29 07:45:02.610557142 -0700
-@@ -126,6 +126,7 @@
-     return 0;
- }
- 
-+#if !defined(__redox__)
- int
- sigemptyset (sigset_t *set)
- {
-@@ -180,6 +181,7 @@
-   *set = ((2U << (NSIG - 1)) - 1) & ~ SIGABRT_COMPAT_MASK;
-   return 0;
- }
-+#endif
- 
- /* Set of currently blocked signals.  */
- static volatile sigset_t blocked_set /* = 0 */;

recipes/tools/diffutils/recipe.toml

@@ -1,25 +0,0 @@
-[source]
-tar = "https://ftp.gnu.org/gnu/diffutils/diffutils-3.6.tar.xz"
-blake3 = "086a95093c15edcdb826e75ff4de6c2213de6fbd2eb13538d07bdc3286dfb4a4"
-patches = ["diffutils.patch"]
-script = """
-autoreconf
-"""
-
-[build]
-template = "custom"
-dependencies = ["relibc"]
-script = """
-DYNAMIC_INIT
-COOKBOOK_CONFIGURE_FLAGS+=(
-    gt_cv_locale_fr=false
-    gt_cv_locale_fr_utf8=false
-    gt_cv_locale_ja=false
-    gt_cv_locale_tr_utf8=false
-    gt_cv_locale_zh_CN=false
-    gl_cv_func_working_mktime=yes
-    ac_cv_func_getprogname=yes
-)
-cookbook_configure
-rm -f "${COOKBOOK_STAGE}/usr/share/info/dir"
-"""