Editor checkpoint: turnout domain service, web->editor rename, Id-1 templates

Checkpoint of the editor branch so work isn't carried loose across a branch
switch. Builds.

- maj0sted turnout geometry moved into the domain: domain::lay_turnout lays the
  diverging path (pre-blade lead, blade at beta, arc of alfa-beta, frog rail) and
  solve_junction is a thin adapter onto it.
- the maj0sted web/ tree renamed to editor/ (namespace and paths) - there is no
  WASM here, it's plain native C++ the editor calls.
- click places the switch at its start (początek rozjazdu); the branch's leaving
  straight is locked tangent to the frog; switches can be slid along the through
  track and flipped L/P.
- Polish turnout templates carry catalogue length (Id-1-consistent lengths), plus
  blade-angle and pre-blade fields (left 0 until the catalogue figures are in).
- TURNOUT_SPEC.md: the Bezier-based runtime/model contract.
- also folds in other pending branch changes (scenery, tests) to leave a clean tree.

maj0sted/tests/CMakeLists.txt

@@ -33,10 +33,10 @@ target_link_libraries(maj0sted_test_render PRIVATE maj0sted::maj0sted)
 target_include_directories(maj0sted_test_render PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
 add_test(NAME render COMMAND maj0sted_test_render)
 
-add_executable(maj0sted_test_web test_web.cpp)
-target_link_libraries(maj0sted_test_web PRIVATE maj0sted::maj0sted)
-target_include_directories(maj0sted_test_web PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
-add_test(NAME web COMMAND maj0sted_test_web)
+add_executable(maj0sted_test_editor test_editor.cpp)
+target_link_libraries(maj0sted_test_editor PRIVATE maj0sted::maj0sted)
+target_include_directories(maj0sted_test_editor PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
+add_test(NAME editor COMMAND maj0sted_test_editor)
 
 add_executable(maj0sted_test_tile_cache test_tile_cache.cpp)
 target_link_libraries(maj0sted_test_tile_cache PRIVATE maj0sted::maj0sted)