UN-4010 [MISC] mark the generated transport private

The generated package is an implementation detail of the facade: nothing outside
`client.py` should import it, and the flat name reads as public API. Rename it to
`_sdk_docstudio` and follow the path through the generator script, the drift
gate, the lint excludes, the vendored-code attributes and the README.

Regenerating into the new path reproduces the tree byte for byte, so the gate
still compares generator output against the spec and nothing else.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_014f9oEEYspPH4fmPULTnLkJ

Author: chandrasekharan-zipstack

.gitattributes

@@ -1 +1 @@
-src/unstract/api_deployments/sdk_docstudio/** linguist-generated=true
+src/unstract/api_deployments/_sdk_docstudio/** linguist-generated=true

.github/workflows/test.yml

@@ -63,5 +63,5 @@ jobs:
       # newly created, which is exactly what a spec growing an endpoint does.
       - name: Fail if the committed SDK is not what the spec generates
         run: |
-          git add -N -- src/unstract/api_deployments/sdk_docstudio
-          git diff --exit-code -- src/unstract/api_deployments/sdk_docstudio
+          git add -N -- src/unstract/api_deployments/_sdk_docstudio
+          git diff --exit-code -- src/unstract/api_deployments/_sdk_docstudio

README.md

@@ -115,7 +115,7 @@ The retry logic uses exponential backoff with full jitter and respects the `Retr
 
 ## Internals
 
-`unstract.api_deployments.sdk_docstudio` is generated from the deployment API's
+`unstract.api_deployments._sdk_docstudio` is generated from the deployment API's
 OpenAPI spec by `tools/gen_sdk.sh` and is an implementation detail of the
 transport. `APIDeploymentsClient` is the supported surface — import from it, not
 from the generated tree, which is regenerated wholesale whenever the spec moves.

pyproject.toml

@@ -70,7 +70,7 @@ lint = [
 line-length = 88
 # Generated and vendored code is overwritten wholesale by its refresh script, so
 # a lint finding there can never be fixed in place.
-extend-exclude = ["src/unstract/api_deployments/sdk_docstudio", "tests/baseline"]
+extend-exclude = ["src/unstract/api_deployments/_sdk_docstudio", "tests/baseline"]
 
 [tool.ruff.lint]
 select = ["E", "F", "W", "I"]