Blender Git Loki

Fix #30958: Right click menu and add shortcut for importers/exporters doesn't work

This was caused by how keymap is guessing for importer/exporter:

- In some cases if detected wrong keymap like for IMPORT_CURVE_OT_svg
curve editing context was used because of CURVE_OT substring in
operator name
- In other cases no keymap was detected because of substrings
WM_keymap_guess_opname cheched.

Fixed by using Window keymap for any operator with EXPORT_/IMPORT_ substring
which seems to detect importer/exporter operator and only them nicely.