Custom lifetime for OAuth access tokens

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By default, OAuth access tokens in GitLab expire after two hours. In GitLab 19.1, instance administrators on GitLab Self-Managed and GitLab Dedicated can set a custom lifetime for new OAuth access tokens. You can configure any value from 300 to 7200 seconds. This helps you enforce shorter-lived tokens for security-sensitive OAuth integrations, including MCP clients, without changing the behavior of existing tokens.