Suggestions for additional symbols and clearer Unicode documentation

[fenixero]

While implementing Engram-ES, I noticed that some symbol definitions can be interpreted in different ways.

For example:

AltGr + . = • (middle dot, or "interpunct")

The character shown is U+2022 BULLET (•), while the description refers to U+00B7 MIDDLE DOT (·). Most users would probably infer the intended meaning from context, but implementers may not.

Because of that, it might be helpful to include the Unicode code point alongside every special symbol in the documentation. Something like:

AltGr + . = • (U+2022 BULLET)

This would remove ambiguity and make firmware implementations, alternative layouts, and cross-platform support easier to reproduce consistently.

It could also be useful to briefly document the rationale behind some of the less obvious symbols. For example, I assume the inclusion of • is motivated by its common use in Markdown bullet lists, but having that noted explicitly would help future readers understand the design choices.

Additionally, since $, €, and £ are already included, it might be worth considering the addition of:

¥ (U+00A5 YEN SIGN), which is available in several international keyboard layouts as ES.

I noticed that ¢, º, and ª appear in Appendix 2 of the Engram study, but they don't appear in the current Engram-es layout. Were these characters considered during the optimization process but ultimately left out of the final layout?