Merge jinja and cmake generators - first stage

Upgrade merge platforms, remove SubDirs from platform

Merge almost all cmake generator logic to jinja generator
e83692792026885a45cb7eb985d1bbba6eea373d

build/export_generators/gradle/generator.toml

@@ -1,3 +1,5 @@
+ignore_platforms = true
+
 [root]
 template="settings.gradle.kts.jinja"
 copy=[

build/export_generators/ide-gradle/generator.toml

@@ -1,4 +1,5 @@
 use_managed_peers_closure = true
+ignore_platforms = true
 
 [root]
 template="settings.gradle.kts.jinja"