bug(ios): Key processing with text selection problems

### Describe the bug

The test cases for the https://github.com/keymanapp/keyman/issues/9073 with legacy apps show some limitations.

See https://github.com/keymanapp/keyman/issues/9073#issuecomment-1801356344 for the test cases and the [google doc](https://docs.google.com/spreadsheets/d/1NDO82y77C45pw_ZcMPcD36NZ4VUy9hQcuByieyeJVtM/edit?usp=sharing) for the test results.

Keyman 17.0.218-alpha
iOS 16.6
iPhone 13 Mobile
Google Chrome 119.0.6045.169

### Reproduce the bug

Failed Tests:
----------------------------------------------------------------------
1. (T03) ⁞^⁞ in doc, selection as indicated, typing Shift+A.
Expected result: A⁞
Actual results: Â
2. (T04) ^⁞X⁞ in doc. Typing Shift+A.
Expected result: Â⁞
Actual result: ^A
3. (T05) ^⁞X the quick brown fox⁞ in doc. Typing Shift+A.
Expected result: Â⁞
Actual result: ^A
4. (T12) a→⁞ in doc (i.e. A followed by TAB. With text_selection_tests_keyboard you can press T to get the TAB character.).
Typing BKSP.
Expected result: a⁞
Actual result: If I press T to get the TAB character, the page no longer displayed the cursor and the keyboard.
5. (T14) Type A followed by [K_BKQUOTE] and B and C.
Press BKSP twice.
Expected result: ok1
Actual result: a'
6. (T15) Type X, A followed by [K_BKQUOTE] and B. Select B (Xa⁞b⁞).
Press BKSP twice.
Expected result: X⁞
Actual result: Xa
7. (T16) Type X, A followed by [K_BKQUOTE] and B. Select B (Xa⁞b⁞).
Press BKSP then O.
Expected result: Xao⁞
Actual result: Xa'o
8. (T61) Hello ⁞world⁞ in doc.
Expected results: lowercase predictions
Actual result: No lowercase predictions
9. (T62) Hello. ⁞world⁞ in doc.
Expected results: uppercase predictions
Actual result: No uppercase predictions

### Expected behavior

_No response_

### Related issues

#9073 #10093

### Keyman apps

- [ ] Keyman for Android
- [X] Keyman for iPhone and iPad
- [ ] Keyman for Linux
- [ ] Keyman for macOS
- [ ] Keyman for Windows
- [ ] Keyman Developer
- [ ] KeymanWeb
- [ ] Other - give details at bottom of form

### Keyman version

17.0.218-alpha

### Operating system

iOS 16.6

### Device

iPhone 13

### Target application

_No response_

### Browser

Chrome browser

### Keyboard name

_No response_

### Keyboard version

_No response_

### Language name

_No response_

### Additional context

_No response_