Fix Tesla Fleet OAuth scope refresh during reauth

[Bre77]

Proposed change

Add prompt_missing_scopes=true to Tesla Fleet OAuth authorization requests so reauthentication can refresh newly enabled Tesla API scopes instead of silently reusing an older grant. Update the Tesla Fleet config-flow copy to explain that reauthentication refreshes granted scopes and that users should reauthenticate after enabling additional Tesla API permissions. Extend the config-flow test to assert the new authorization parameter.

Type of change

• Bugfix (non-breaking change which fixes an issue)
• Dependency upgrade
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue:
• This PR is related to issue: Missing vehicle charging commands scope for charge current #166692
• Link to documentation pull request:
• Link to developer documentation pull request:
• Link to frontend pull request:

Checklist

• I understand the code I am submitting and can explain how it works.
• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
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• The code has been formatted using Ruff (ruff format homeassistant tests)
• Tests have been added to verify that the new code works.
• Any generated code has been carefully reviewed for correctness and compliance with project standards.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io

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  Updated and included derived files by running: python3 -m script.hassfest.
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  Updated by running python3 -m script.gen_requirements_all.
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[Copilot]

Pull request overview

This PR adds the prompt_missing_scopes: "true" parameter to Tesla Fleet OAuth authorization requests to enable reauthentication to refresh newly enabled Tesla API scopes. It also updates user-facing documentation to explain the reauthentication mechanism and adds corresponding test coverage.

Changes:

• Added prompt_missing_scopes: "true" OAuth parameter to the authorization request in oauth.py to allow users to grant additional scopes during reauthentication
• Updated config flow strings to explain that reauthentication refreshes granted scopes, including newly enabled ones
• Extended config flow tests to assert the presence of the new prompt_missing_scopes parameter

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
homeassistant/components/tesla_fleet/oauth.py	Added prompt_missing_scopes parameter to OAuth extra_authorize_data
homeassistant/components/tesla_fleet/strings.json	Updated user documentation explaining scope refresh during reauth
tests/components/tesla_fleet/test_config_flow.py	Added assertion verifying the prompt_missing_scopes parameter in OAuth URL