Make application password uuid/name nullable to avoid Gson NPE

[adalpari]

Description

ApplicationPasswordCreationResponse and ApplicationPasswordsFetchResponse are
deserialized by Gson, which populates fields via reflection. When the server omits a
field, Gson assigns null to it even though the Kotlin property is declared non-null —
the violated invariant then surfaces as a latent NullPointerException when the value
is later dereferenced (e.g. it.uuid when building the UUID/creation payloads).

This follows up on a review comment from #22953 (the Site Settings GBKit toggle RC crash
fix), where the same latent issue was flagged but deferred as out of scope for that
targeted RC fix.

Changes (scoped to uuid and name only):

• Make uuid and name nullable in ApplicationPasswordCreationResponse and
  ApplicationPasswordsFetchResponse.
• Guard the uuid dereferences in WPApiApplicationPasswordsRestClient (create, fetch,
  and introspect paths) and JetpackApplicationPasswordsRestClient (create and fetch
  paths) so a missing uuid returns the existing error payload instead of crashing.
• name is only used in null-safe == comparisons, so it needs no usage-site guards.

No behavior change for well-formed responses; only the malformed/missing-field path is
affected, which now degrades gracefully to an error payload.

Testing instructions

This is a defensive fix for malformed server responses that can't easily be reproduced
against a real backend. Verify via code review and existing coverage:

1. Run the fluxc unit tests:
   ./gradlew :libs:fluxc:testDebugUnitTest --tests "*ApplicationPassword*"

• Verify application password creation/fetch/delete tests still pass.

2. Sign in to a self-hosted site using application-password auth and confirm login still
   works end to end.

• Verify the application password is created and the site connects normally.

🤖 Generated with Claude Code

[dangermattic]

	1 Message
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[wpmobilebot]

📲 You can test the changes from this Pull Request in WordPress Android by scanning the QR code below to install the corresponding build.

	App Name	WordPress Android
	Build Type	Debug
	Version	pr22968-feff57e
	Build Number	1493
	Application ID	org.wordpress.android.prealpha
	Commit	feff57e
	Installation URL	7ueotfcjj7u3g

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[wpmobilebot]

📲 You can test the changes from this Pull Request in Jetpack Android by scanning the QR code below to install the corresponding build.

	App Name	Jetpack Android
	Build Type	Debug
	Version	pr22968-feff57e
	Build Number	1493
	Application ID	com.jetpack.android.prealpha
	Commit	feff57e
	Installation URL	5m3g9ucs83oko

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[codecov]

Codecov Report

❌ Patch coverage is 0% with 16 lines in your changes missing coverage. Please review.
✅ Project coverage is 37.22%. Comparing base (70613b7) to head (feff57e).

Files with missing lines	Patch %	Lines
...onpasswords/WPApiApplicationPasswordsRestClient.kt	0.00%	7 Missing ⚠️
...passwords/JetpackApplicationPasswordsRestClient.kt	0.00%	5 Missing ⚠️
...ationpasswords/ApplicationPasswordsApiResponses.kt	0.00%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##            trunk   #22968      +/-   ##
==========================================
- Coverage   37.22%   37.22%   -0.01%     
==========================================
  Files        2329     2329              
  Lines      125323   125325       +2     
  Branches    17044    17044              
==========================================
  Hits        46657    46657              
- Misses      74893    74895       +2     
  Partials     3773     3773              

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