Improve consumption of primitive types as body

[noordawod]

Currently, the ApiClient for OkHttp allows sending textual body payloads (MIME=text/plain) only for Strings, but it can be easily adapted to send primitive types too: any character sequence, numbers, and booleans.

This small PR allows doing just that. If the content is not a primitive, then a suitable error is thrown instead.

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---

Summary by cubic

Extend the Kotlin JVM OkHttp ApiClient to support text/plain bodies from primitive values (Char/CharSequence, Number, Boolean via toString); non-primitives now error clearly, logic is consolidated into a single when, and samples are regenerated.

^{Written for commit 40b7d40. Summary will update on new commits.}

[cubic-dev-ai]

10 issues found across 28 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="samples/client/petstore/kotlin-json-request-string/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt">

<violation number="1" location="samples/client/petstore/kotlin-json-request-string/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt:279">
P2: `text/plain` primitive handling excludes `Char`, so single-character bodies still throw `UnsupportedOperationException`.</violation>
</file>

<file name="samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt">

<violation number="1" location="samples/client/echo_api/kotlin-jvm-okhttp/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt:275">
P2: `text/plain` primitive handling claims character support but omits Kotlin `Char`, causing `Char` request bodies to throw.</violation>
</file>

<file name="samples/client/petstore/kotlin-allOf-discriminator/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt">

<violation number="1" location="samples/client/petstore/kotlin-allOf-discriminator/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt:275">
P2: `text/plain` body serialization excludes Kotlin `Char`, contradicting the stated support for characters and causing valid primitive payloads to throw.</violation>
</file>

<file name="samples/client/petstore/kotlin-name-parameter-mappings/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt">

<violation number="1" location="samples/client/petstore/kotlin-name-parameter-mappings/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt:275">
P2: `text/plain` primitive handling omits Kotlin `Char`, causing single-character bodies to throw `UnsupportedOperationException`.</violation>
</file>

<file name="samples/client/petstore/kotlin-string/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt">

<violation number="1" location="samples/client/petstore/kotlin-string/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt:275">
P2: `text/plain` primitive handling claims character support but rejects Kotlin `Char` at runtime.</violation>
</file>

<file name="samples/client/petstore/kotlin-gson/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt">

<violation number="1" location="samples/client/petstore/kotlin-gson/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt:275">
P2: `text/plain` primitive support claims to allow characters but omits Kotlin `Char`, causing valid single-character payloads to fail.</violation>
</file>

<file name="samples/client/others/kotlin-jvm-okhttp-parameter-tests/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt">

<violation number="1" location="samples/client/others/kotlin-jvm-okhttp-parameter-tests/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt:275">
P2: `text/plain` primitive-body handling omits Kotlin `Char`, causing runtime `UnsupportedOperationException` for single-character payloads.</violation>
</file>

<file name="samples/client/petstore/kotlin-kotlinx-datetime/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt">

<violation number="1" location="samples/client/petstore/kotlin-kotlinx-datetime/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt:275">
P2: `text/plain` primitive body handling omits Kotlin `Char`, so single-character payloads are rejected despite claiming character support.</violation>
</file>

<file name="samples/client/others/kotlin-jvm-okhttp-non-ascii-headers/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt">

<violation number="1" location="samples/client/others/kotlin-jvm-okhttp-non-ascii-headers/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt:275">
P2: `text/plain` primitive handling is incomplete: `Char` bodies are rejected because the new type checks omit `Char` even though the code claims to support characters.</violation>
</file>

<file name="samples/client/petstore/kotlin-bigdecimal-default-okhttp4/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt">

<violation number="1" location="samples/client/petstore/kotlin-bigdecimal-default-okhttp4/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt:275">
P2: `text/plain` primitive serialization omits Kotlin `Char`, causing runtime rejection despite claiming character support.</violation>
</file>

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[wing328]

thanks for the contribution, which has been merged