This is needed to release on F-Droid.

Suggest an emoji in addition to the 3 suggested words when the
current word matches an alias in the emoji dictionary, if
available.

* Update cdict

* scripts/subst_of_compose.py: Compute substitutions

from compose mappings. They are used when building dictionaries.

* Add substitutions compose data

* Better suggestion with diacritics

This improves the suggestions for words that contain diacritics and
uppercase letters.

This works by stripping diacritics both when building the dictionaries
(using word aliases added in cdict: https://github.com/Julow/cdict/pull/3)
and during lookup. Cdict then takes care of resolving the correct word.

The substitutions are generated using mappings from `fn`, `shift` and
all the `accent_*` modifiers into srcs/compose/substitutions.json
This can be updated easily when more mappings are added.

This adds dictionary-based spell checking to the keyboard. The keyboard looks at the word being typed and matches it against a dictionary to either complete the rest of the word or find alternative spellings.

The core of this feature is implemented in cdict, which is included as a
submodule in vendor/cidct.

Cdict is developped at https://github.com/Julow/cdict
The dictionaries are hosted at https://github.com/Julow/Unexpected-Keyboard-dictionaries/
The wordlists used to build the dictionaries are the same ones used by
HeliBoard from https://codeberg.org/Helium314/aosp-dictionaries

- Add an activity accessible from the launcher app that lists available
  dictionaries with a download button.
  The DictionaryListView view shows the list of available dictionaries and
  handles downloading and installing them.

- The Dictionaries class manages installed dictionaries. Dictionaries are
  installed as individual files into the app's private directory.

- Available dictionaries are listed in dictionaries.xml, which is generated
  when building Unexpected-Keyboard-dictionaries.
  method.xml mentions the dictionary name for each locales.