generate mintops.ts to artifacts/bin/native/generated

- Drive the generation from wasm.proj (driving it from cmake is wrong,
because the cmake build runs after rollup)
- Use the tsconfig rootDirs option to specify where to find the
files (runtime dir and also artifacts/bin/native/generated)
- Also due to rollup issues, specify rootDirs and include in
rollup.config.js - otherwise the rollup typescript plugin doesn't seem
to kick in, and barebones rollup gets confused when parsing .ts files
- The outDir option in tsconfig.json had to be deleted to make rollup
work.  But it was also unused since rollup controls where the ts
plugin is supposed to emit its output
- VS Code understands the tsconfig.json changes and can follow
references to the artifacts/.../generated folder

Note that Release and Debug builds both dump the generates mintops.ts
in the same folder.  This seems ok for now since there's no special
debug-only opcodes.  (Also VS Code has no idea about configurations,
so it has to be done this way or else it won't be able to find the .ts file)

src/mono/wasm/runtime/CMakeLists.txt

@@ -36,13 +36,6 @@ set_target_properties(dotnet PROPERTIES
 
 set(ignoreMeWasmOptFlags "${CONFIGURATION_WASM_OPT_FLAGS}")
 
-add_custom_target(GENERATE_MINTOPS_TYPESCRIPT ALL
-    ${Python3_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/genmintops.py "${CMAKE_CURRENT_SOURCE_DIR}/../../mono/mini/interp/mintops.def" "${CMAKE_CURRENT_SOURCE_DIR}/mintops.ts"
-    DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/genmintops.py ${CMAKE_CURRENT_SOURCE_DIR}/../../mono/mini/interp/mintops.def
-    BYPRODUCTS ${CMAKE_CURRENT_SOURCE_DIR}/mintops.ts
-    VERBATIM
-)
-
 if(CMAKE_BUILD_TYPE STREQUAL "Release")
     add_custom_command(TARGET dotnet
                         POST_BUILD COMMAND ${EMSDK_PATH}/upstream/bin/wasm-opt --enable-exception-handling ${CONFIGURATION_WASM_OPT_FLAGS} --strip-dwarf ${NATIVE_BIN_DIR}/dotnet.wasm -o ${NATIVE_BIN_DIR}/dotnet.wasm

src/mono/wasm/runtime/genmintops.py

@@ -46,14 +46,15 @@
 }};
 """
 
-dest = open(output_ts_path, 'r')
-if (dest.read() == generated):
-    print("mintops.ts up to date, exiting")
-    exit(0)
-
-dest.close()
-dest = open(output_ts_path, 'w')
-dest.write(generated)
+os.makedirs(os.path.dirname(output_ts_path), exist_ok=True)
+try:
+    with open(output_ts_path, 'r') as dest:
+        if (dest.read() == generated):
+            print("mintops.ts up to date, exiting")
+            exit(0)
+except FileNotFoundError:
+    pass
+with open(output_ts_path, 'w') as dest:
+    dest.write(generated)
 print("mintops.ts generated")
-dest.close()
 exit(0)