Full input support

[TheRedDeveloper]

Summary

Implement comprehensive text input support across all platforms, including IME composition, preedit/candidate display, dead keys, and voice-to-text preedit. This work lives primarily in macroquad-ply and miniquad-ply rather than in the engine itself. This supersedes #65.

Notes

• This is internal work; there is no concrete implementation plan for outsiders and no outside contributions are expected.
• Because there is no outward-facing API change, this issue is not subject to the usual API design review process.
• Work has already started on this a long while ago in Text input sequence not correct #65.

TODO

• Windows
• Linux
  • X11
  • Wayland
• Android
• Web
• MacOS
• iOS

[TheRedDeveloper]

Full input support is done on Linux (TheRedDeveloper/miniquad-fix@24388d3) now!

It was already done on Windows (TheRedDeveloper/miniquad-fix@10ad704), has been connected into macroquad (TheRedDeveloper/macroquad-fix@39364e0) and connected into ply-engine (52a4bde)