* docs(providers): note that ANTHROPIC_API_KEY requires an API account, not a subscription
Anthropic subscription users authenticate via OAuth, not an API key,
causing a silent failure when creating the provider. Adds a Note callout
in the provider type table and quickstart guide directing subscription
users to generate an API key from console.anthropic.com.
Closes#620
* docs(providers): fix Note placement and remove subscription brand names
Move the Note callout in manage-providers.mdx to after the complete
provider type table so it does not break table rendering. Remove
subscription brand names from both Note callouts.