Return config entry details for 1-step config flows

[emontnemery]

Proposed change

Return config entry details for 1-step config flows

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Breaking change (fix/feature causing existing functionality to break)
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Additional information

• This PR is related to issue: Return config entry details after creation #48316

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[probot-home-assistant]

Hey there @home-assistant/core, mind taking a look at this pull request as its been labeled with an integration (config) you are listed as a codeowner for? Thanks!
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[MartinHjelmare]

When does the frontend use the index view post request?

[emontnemery]

ConfigManagerFlowIndexView / /api/config/config_entries/flow should be used to initiate a config flow, then ConfigManagerFlowResourceView / /api/config/config_entries/flow/{flow_id} is used when finishing the flow.
@bramkragten can you confirm that's how it's used?

[bramkragten]

When does the frontend use the index view post request?

When we create a new config flow