Conjugation and declension

[catreedle]

Contributor checklist

• This pull request is on a separate branch and not the main branch
• I have tested my code with the xcodebuild and swiftlint --strict commands as directed in the testing section of the contributing guide

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Description

This PR migrates the iOS keyboard's conjugation and declension systems from hardcoded implementations to a dynamic, JSON contract-based architecture.

Added:

• Keyboards/KeyboardsBase/DynamicConjugationViewController.swift - Dynamic view controller that handles both conjugation and declension navigation

• Keyboards/DataManager/ConjugationManager.swift - Parses conjugation JSON contracts and builds navigation structures

• Keyboards/DataManager/DeclensionManager.swift - Parses declension JSON contracts and builds navigation structures

• Keyboards/KeyboardsBase/NavigationStructure.swift - Defines NavigationNode and NavigationLevel structures for recursive navigation

• Keyboards/DataContracts/de_declensions.json - German declension contract

• Keyboards/DataContracts/ru_declensions.json - Russian declension contract

• Updated Keyboards/KeyboardsBase/KeyboardViewController.swift to use new dynamic system, removed old hardcoded conjugation/declension state

• Removed stale variables and functions from Keyboards/KeyboardsBase/ScribeFunctionality/Conjugate.swift

Related issue

• Data contract #587

[github-actions]

Thank you for the pull request! 💙

The Scribe-iOS team will do our best to address your contribution as soon as we can. If you're not already a member of our public Matrix community, please consider joining! We'd suggest that you use the Element client as well as Element X for a mobile app, and definitely join the General and iOS rooms once you're in. Also consider attending our bi-weekly Saturday dev syncs. It'd be great to meet you 😊

Note

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[github-actions]

Maintainer Checklist

The following is a checklist for maintainers to make sure this process goes as well as possible. Feel free to address the points below yourself in further commits if you realize that actions are needed :)

• Tests for changes have been written and the CI unit test, linting and formatting workflows within the PR checks do not indicate new errors in the files changed

• The CHANGELOG has been updated with a description of the changes for the upcoming release and the corresponding issue (if necessary)