feat: Add client_info support for custom telemetry in Authentication and Management clients

[kishore7snehil]

Changes

• Add optional client_info dict param to RestClientOptions to override the default telemetry payload
• Use provided client_info as the Auth0-Client header value in RestClient when telemetry is enabled
• Thread client_info param through AuthenticationBase constructor to RestClientOptions
• Add client_info param to ManagementClient - encodes and merges into headers dict
• Add client_info param to AsyncManagementClient with identical behavior
• telemetry=False still takes precedence and suppresses all telemetry headers
• User-Agent header remains Python/{version} regardless of client_info
• No changes to any Fern-generated files (client.py, client_wrapper.py, http_client.py)

Usage

# Authentication
from auth0.authentication import GetToken

client = GetToken(
    "tenant.auth0.com",
    client_id="YOUR_CLIENT_ID",
    client_info={"name": "auth0-ai-langchain", "version": "1.0.0", "env": {"python": "3.11.0"}},
)

# Management
from auth0.management import ManagementClient

client = ManagementClient(
    domain="tenant.auth0.com",
    token="YOUR_TOKEN",
    client_info={"name": "auth0-ai-langchain", "version": "1.0.0", "env": {"python": "3.11.0"}},
)

[duedares-rvj]

LGTM