chore(api): correct fine-tuning bounds and Realtime response reference (openai#3949)

## Summary

Corrects fine-tuning numeric bounds and Realtime client-secret response
alternatives in the Python API reference.

## Changes

- Use OpenAPI 3.1 numeric exclusive bounds for fine-tuning parameters.
- Identify realtime and transcription session alternatives in
client-secret responses.






## Why

The API reference used boolean `exclusiveMinimum` values, which are
invalid in OpenAPI 3.1. This corrects seven numeric lower bounds and
restores their existing `auto` defaults. Explicit discriminator mappings
also identify the existing `realtime` and `transcription` alternatives
in client-secret responses.

This is a reference-only correction: SDK source, public types,
dependencies, and request/response serialization are unchanged.

Source: [published OpenAPI
correction](openai/openai-openapi@946e365).

## Compatibility review

Reviewed head `add92714d353df33e1ee98a604800ce8b6e6d42d` against base
`4d1274681db7f34f671ff9e71adc1461d22a927b`.

- The complete tree diff contains only `.castiron.stats.yml` and
`api_reference/openapi.transformed.yml`. All SDK source, public
signatures, related model types, serializers, dependencies, and
package/build configuration are unchanged. Neither changed file is
consumed by the SDK runtime or enters its normal distributed code.
- Paired baseline/candidate Python client and model probes pass (183
cases per revision, identical results).
- The transformed reference passes 464 focused schema cases, including
actual enclosing requests/responses, lower/upper boundaries, `auto`,
omission, and both Realtime response variants.
- [Current-head
CI](https://github.com/openai/openai-python/actions/runs/35922654398)
passes.

Scope: this establishes no identified SDK-package compile-time or
runtime compatibility regression from this patch. Tools that directly
read the OpenAPI reference (validators, mock servers, or third-party
generators) can observe the corrected bounds, defaults, and explicit
mappings; those integrations are a separate compatibility surface. No
deployed-service test or package release is claimed.

Co-authored-by: markstuart-oai <323302876+markstuart-oai@users.noreply.github.com>

Author: markstuart-oai

.castiron.stats.yml

@@ -1,8 +1,8 @@
 schema_version: 1
-generation_id: d9e3b632-5822-43f8-a0de-0cd04d09db33
-openapi_spec_hash: 687580b2f55d2dada661f0387a4b3e0d
-openapi_transformed_spec_hash: 904296217a5077aa14766c6c58aa87d9
+generation_id: aa310748-8aec-4537-9913-7c71cb2237cb
+openapi_spec_hash: 3fdbf56dcaf85efe1e621db8067f829a
+openapi_transformed_spec_hash: 3ff7c45d6856b5ffccfd73b63ee4263d
 config_hash: 84cdcc959ee7140cc9a65e9b642c097b
-codegen_sha: 41ac0d43560df6c0983b529a6112e2c437ead2d1
+codegen_sha: 7b758af07cc10c9cf05f332897c9b75f85162bf3
 codegen_hash: 614193cc88f476d3dbfe7d149d8adf21489f235af4454fb1e93628fe43e1e351
-public_codegen_sha: 2722089d4e9342c45f1ddbda6e7b4b72511d961f
+public_codegen_sha: 7eba580f1b2d7eb434697db16f576022d16b0388

api_reference/openapi.transformed.yml

@@ -36954,15 +36954,15 @@ components:
               description: |
                 Scaling factor for the learning rate. A smaller learning rate may be useful to avoid
                 overfitting.
+              default: auto
               anyOf:
               - type: string
                 enum:
                 - auto
                 x-stainless-const: true
                 title: Auto
               - type: number
-                minimum: 0
-                exclusiveMinimum: true
+                exclusiveMinimum: 0
             n_epochs:
               description: |
                 The number of epochs to train the model for. An epoch refers to one full cycle
@@ -41281,15 +41281,15 @@ components:
         beta:
           description: |
             The beta value for the DPO method. A higher beta value will increase the weight of the penalty between the policy and reference model.
+          default: auto
           anyOf:
           - type: string
             enum:
             - auto
             x-stainless-const: true
           - type: number
-            minimum: 0
             maximum: 2
-            exclusiveMinimum: true
+            exclusiveMinimum: 0
         batch_size:
           description: |
             Number of examples in each batch. A larger batch size means that model parameters are updated less frequently, but with lower variance.
@@ -41305,14 +41305,14 @@ components:
         learning_rate_multiplier:
           description: |
             Scaling factor for the learning rate. A smaller learning rate may be useful to avoid overfitting.
+          default: auto
           anyOf:
           - type: string
             enum:
             - auto
             x-stainless-const: true
           - type: number
-            minimum: 0
-            exclusiveMinimum: true
+            exclusiveMinimum: 0
         n_epochs:
           description: |
             The number of epochs to train the model for. An epoch refers to one full cycle through the training dataset.
@@ -41369,14 +41369,14 @@ components:
         learning_rate_multiplier:
           description: |
             Scaling factor for the learning rate. A smaller learning rate may be useful to avoid overfitting.
+          default: auto
           anyOf:
           - type: string
             enum:
             - auto
             x-stainless-const: true
           - type: number
-            minimum: 0
-            exclusiveMinimum: true
+            exclusiveMinimum: 0
         n_epochs:
           description: |
             The number of epochs to train the model for. An epoch refers to one full cycle through the training dataset.
@@ -41402,15 +41402,15 @@ components:
         compute_multiplier:
           description: |
             Multiplier on amount of compute used for exploring search space during training.
+          default: auto
           anyOf:
           - type: string
             enum:
             - auto
             x-stainless-const: true
           - type: number
-            minimum: 0.00001
             maximum: 10
-            exclusiveMinimum: true
+            exclusiveMinimum: 0.00001
         eval_interval:
           description: |
             The number of training steps between evaluation runs.
@@ -41469,14 +41469,14 @@ components:
         learning_rate_multiplier:
           description: |
             Scaling factor for the learning rate. A smaller learning rate may be useful to avoid overfitting.
+          default: auto
           anyOf:
           - type: string
             enum:
             - auto
             x-stainless-const: true
           - type: number
-            minimum: 0
-            exclusiveMinimum: true
+            exclusiveMinimum: 0
         n_epochs:
           description: |
             The number of epochs to train the model for. An epoch refers to one full cycle through the training dataset.
@@ -41649,15 +41649,15 @@ components:
               description: |
                 Scaling factor for the learning rate. A smaller learning rate may be useful to avoid
                 overfitting.
+              default: auto
               anyOf:
               - type: string
                 enum:
                 - auto
                 x-stainless-const: true
                 title: Auto
               - type: number
-                minimum: 0
-                exclusiveMinimum: true
+                exclusiveMinimum: 0
             n_epochs:
               description: |
                 The number of epochs to train the model for. An epoch refers to one full cycle
@@ -51336,6 +51336,9 @@ components:
             The session configuration for either a realtime or transcription session.
           discriminator:
             propertyName: type
+            mapping:
+              realtime: '#/components/schemas/RealtimeSessionCreateResponseGA'
+              transcription: '#/components/schemas/RealtimeTranscriptionSessionCreateResponseGA'
           anyOf:
           - $ref: '#/components/schemas/RealtimeSessionCreateResponseGA'
           - $ref: '#/components/schemas/RealtimeTranscriptionSessionCreateResponseGA'