docs: fix documentation drift in README and examples

[rmad17]

📋 Changes

This PR fixes documentation drift across README.md and the examples/ documentation for the current 1.0.0b13 API surface. A full audit found and addressed 9 issues: 6 P1 copy-paste/runtime failures and 3 P3 style
or consistency fixes.

Fixes

• Corrected the installation command in README.md from poetry install auth0-server-python to poetry add auth0-server-python
• Quoted the redirect_uri dictionary key in README.md so the Python snippet no longer raises NameError
• Fixed ServerClient imports in examples/ClientInitiatedBackChannelLogin.md and examples/MultipleCustomDomains.md to use from auth0_server_python.auth_server import ServerClient
• Fixed store imports in examples/ConfigureStore.md to use from auth0_server_python.store import ...
• Added the missing comma between audience= and scope= in examples/RetrievingData.md
• Updated SDK examples in examples/RetrievingData.md from JS-style naming to the actual Python API names: server_client, get_user, get_access_token, and login_hint
• Hoisted inline import json statements out of method bodies in examples/ConfigureStore.md
• Aligned examples with the package’s current import paths and Python naming conventions

Testing

• This change adds documentation correction coverage through snippet verification
• Every corrected import/snippet was validated against the current source tree

Contributor Checklist

• I agree to adhere to the Auth0 General Contribution Guidelines (https://github.com/auth0/open-source-template/blob/master/GENERAL-CONTRIBUTING.md).
• I agree to uphold the Auth0 Code of Conduct (https://github.com/auth0/open-source-template/blob/master/CODE-OF-CONDUCT.md).

[kishore7snehil]

LGTM!