fix(web): retry importScripts NetworkErrors in attempt to mitigate errors loading models 🏠

[mcdurdin]

A deeper workaround is applied in 19.0 (see for example #16565, #16586) but for 18.0, this is an attempt to bypass the constant issue of models failing to load with Chrome 152 and later versions, by retrying on failure.

Relates-to: #13862 (may fix)

User Testing

• TEST_MODELS_ANDROID: On Keyman for Android, verify that text input and predictive text is working as normal.
• TEST_MODELS_IOS: On Keyman for iOS, verify that text input and predictive text is working as normal.

[keymanapp-test-bot]

User Test Results

Test specification and instructions

• ✅ TEST_MODELS_ANDROID (PASSED) (notes)
• ✅ TEST_MODELS_IOS (PASSED) (notes)

Test Artifacts

• Android
  • Keyman for Android apk
  • FirstVoices Keyboards for Android apk
  • KeyboardHarness apk
  • KMSample1 apk
  • KMSample2 apk
• Developer
  • Keyman Developer
  • Compiler Regression Tests
  • kmcomp.zip
• iOS
  • Keyman for iOS (simulator image)
  • FirstVoices Keyboards for iOS (simulator image)
• Keyboards
  • Test Keyboards
• Web
  • KeymanWeb Test Home
• Windows
  • Keyman for Windows
  • FirstVoices Keyboards for Windows
  • Text Editor (ARM64)
  • Text Editor (x64)
  • Text Editor (x86)

[jahorton]

Possible issue - didn't we set Android to auto-reload its host WebView when encountering Web engine errors? Wouldn't that trigger on the first error output below if so?

I should probably double-check whether or not that's still in place.

[jahorton]

I'll put together a 🍒 for #16548 to go alongside this; it'll cut off the highly-correlated paired error we've been getting.

[mcdurdin]

Possible issue - didn't we set Android to auto-reload its host WebView when encountering Web engine errors? Wouldn't that trigger on the first error output below if so?

I should probably double-check whether or not that's still in place.

Just tested: console.warn is reported through to sentry as a warning but doesn't reload the page.

[Meng-Heng]

Test Specs

1. Keyman 18.0.250-test-16604
2. XCode iPad Air 11-inch (M3)
3. Samsung Galaxy A06, Android v15.0

Test Results

• TEST_MODELS_ANDROID (PASSED):

1. Launch Keyman with the default EuroLatin (SIL), check to see "Prediction with corrections" is enabled
2. Start typing and applying predictive text
3. Apply reversion and using backspace
4. VERIFIED: No error indications, and work as expected.

• TEST_MODELS_IOS (PASSED):

1. Launch Keyman with the default EuroLatin (SIL), check to see "Prediction" & "Corrections" are enabled
2. Start typing and applying predictive text
3. Apply reversion and using backspace
4. VERIFIED: No error indications, and work as expected.

[keyman-server]

Changes in this pull request will be available for download in Keyman version 18.0.250