Migrate VertexAI serialization to be localized

[emilypgoogle]

There are some considerations to how this should be finalized. Current implementation details that I've decided on which we can change:

• Based on the example doc, all classes Foo have been renamed InternalFoo
• All internal serialization classes, where relevant, are moved to inner classes of their API counterparts
• All classes only used as child fields for serialization classes have been moved to inner classes of those classes
• All toPublic and toInternal methods on API and serialization classes have been moved inside of those classes and conversions.kt has been mostly emptied.
• A few serialization classes do not have API equivalents and are left in a Types.kt file

Possible changes:

• Change all InternalFoo classes to have the same name, referenced as Foo.Internal rather than Foo.InternalFoo. This will probably make the codebase feel cleaner, but I'll wait for opinions on it
• Move serialization only classes out of the internal serialization classes, either to inner classes of the API classes or top level classes themselves.
• For classes that have serializers, rename serializers from InternalFooSerializer to Serializer for example Foo.InternalFoo.Serializer or Foo.Internal.Serializer instead of Foo.InternalFoo.InternalFooSerializer or Foo.Internal.InternalFooSerializer

[github-actions]

Release note changes

No release note changes were detected. If you made changes that should be
present in the next release, ensure you've added an entry in the appropriate
CHANGELOG.md file(s).

[github-actions]

Vertex AI Mock Responses Check ⚠️

A newer major version of the mock responses for Vertex AI unit tests is available. update_responses.sh should be updated to clone the latest version of the responses: v5.3

[google-oss-bot]

	1 Warning
⚠️	Did you forget to add a changelog entry? (Add the 'no-changelog' label to the PR to silence this warning.)

Generated by 🚫 Danger

[google-oss-bot]

Coverage Report ¹

Affected Products

No changes between base commit (f2d05d6) and merge commit (3f27cf8).

Test Logs

• Base (f2d05d6): https://github.com/firebase/firebase-android-sdk/actions/runs/13037675270
• Merge (3f27cf8): https://github.com/firebase/firebase-android-sdk/actions/runs/13039435927

1. https://storage.googleapis.com/firebase-sdk-metric-reports/XMoKV111rm.html

[github-actions]

Test Results

 20 files  ±0   20 suites  ±0   12s ⏱️ ±0s
113 tests ±0  113 ✅ ±0  0 💤 ±0  0 ❌ ±0 
226 runs  ±0  226 ✅ ±0  0 💤 ±0  0 ❌ ±0 

Results for commit f618e00. ± Comparison against base commit f2d05d6.

♻️ This comment has been updated with latest results.

[daymxn]

This doesn't currently compile, as there's some imports and usages that need to be updated. Like:

- private fun InternalGenerateContentResponse.validate()
+ private fun GenerateContentResponse.InternalGenerateContentResponse.validate()

Also, (and this probably a convo for @rlazo too), any reason we want the fully qualified names over something like Internal?

Current:

public class FunctionDeclaration(
  internal val name: String,
  internal val description: String,
  internal val parameters: Map<String, Schema>,
  internal val optionalParameters: List<String> = emptyList(),
) {
  internal val schema: Schema =
    Schema.obj(properties = parameters, optionalProperties = optionalParameters, nullable = false)

  internal fun toInternal() =
    InternalFunctionDeclaration(name, "", schema.toInternal())

  @Serializable
  internal data class InternalFunctionDeclaration(
    val name: String,
    val description: String,
    val parameters: Schema.InternalSchema
  )
}

With internal naming:

public class FunctionDeclaration(
  internal val name: String,
  internal val description: String,
  internal val parameters: Map<String, Schema>,
  internal val optionalParameters: List<String> = emptyList(),
) {
  internal val schema: Schema =
    Schema.obj(properties = parameters, optionalProperties = optionalParameters, nullable = false)

  internal fun toInternal() =
   Internal(name, "", schema.toInternal())

  @Serializable
  internal data class Internal(
    val name: String,
    val description: String,
    val parameters: Schema.InternalSchema
  )
}

So its usage would be like this:

- FunctionDeclaration.InternalFunctionDeclaration(...)
+ FunctionDeclaration.Internal(...)

[rlazo]

• ther to inner classes of the API classes or top level classes themselves.

+1 to Call inner classes Internal rather than the full name, and the same applies to serializers.

[google-oss-bot]

Size Report ¹

Affected Products

• firebase-vertexai

  Type	Base (f2d05d6)	Merge (3f27cf8)	Diff
  aar	477 kB	490 kB	+13.2 kB (+2.8%)
  apk (aggressive)	1.09 MB	1.32 MB	+223 kB (+20.4%)
  apk (release)	9.15 MB	9.16 MB	+6.27 kB (+0.1%)

Test Logs

• Base (f2d05d6): https://github.com/firebase/firebase-android-sdk/actions/runs/13037675270
• Merge (3f27cf8): https://github.com/firebase/firebase-android-sdk/actions/runs/13039435927

1. https://storage.googleapis.com/firebase-sdk-metric-reports/n0LyJ4ToEP.html

[daymxn]

+1
Besides the test failures, LGTM. I defer to @rlazo for the final approval.

[daymxn]

LGTM so long as the tests pass