layout: restructure into src/ tests/ android/ scripts/ tools/

- extension/src/{port,platform,codepage} -> src/; native_render -> src/host
  (+ dxt, shaders/); libgr2 -> src/gr2; extension/third_party -> third_party
- extension/tests -> tests/port, libgr2/tests -> tests/gr2
- android-native -> android (build.sh, push-client.sh moved in)
- script -> scripts; tools/40250 -> tools/server; oracle -> tools/granny-oracle;
  perf tools -> tools/perf
- all build trees under build/ (native, release, android, port-gate)
- xrender:: CMake aliases -> mt::; port-map ledger impl paths rewritten

No code changes. ctest 15/15, port_gate macos+android PASS, port_map check 0 errors.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

third_party/cpython-2.7.18/Misc/README.OpenBSD

@@ -0,0 +1,38 @@
+
+2005-01-08
+
+If you are have a problem building on OpenBSD and see output like this
+while running configure:
+
+checking curses.h presence... yes
+configure: WARNING: curses.h: present but cannot be compiled
+configure: WARNING: curses.h: check for missing prerequisite headers?
+configure: WARNING: curses.h: see the Autoconf documentation
+configure: WARNING: curses.h: section "Present But Cannot Be Compiled"
+configure: WARNING: curses.h: proceeding with the preprocessor's result
+configure: WARNING: curses.h: in the future, the compiler will take precedence
+
+there is likely a problem that will prevent building python.  
+If you see the messages above and are able to completely build python,
+please tell python-dev@python.org indicating your version of OpenBSD
+and any other relevant system configuration.
+
+The build error that occurs while making may look something like this:
+
+    /usr/include/sys/event.h:53: error: syntax error before "u_int"
+    /usr/include/sys/event.h:55: error: syntax error before "u_short"
+
+To fix this problem, you will probably need update Python's configure
+script to disable certain options.  Search for a line that looks like:
+
+    OpenBSD/2.* | OpenBSD/3.@<:@012345678@:>@)
+
+If your version is not in that list, e.g., 3.9, add the version
+number.  In this case, you would just need to add a 9 after the 8.
+If you modify configure.ac, you will need to regenerate configure
+with autoconf.
+
+If your version is already in the list, this is not a known problem.
+Please submit a bug report here:
+
+    http://sourceforge.net/tracker/?group_id=5470&atid=105470