fix: config parsing so viper works

[gusfcarvalho]

No description provided.

[Copilot]

Pull request overview

This PR refactors the SSO configuration to use a map-based structure for providers instead of an array, enabling proper parsing with Viper. The changes remove custom environment variable expansion logic in favor of Viper's built-in functionality.

• Changed Providers from []SSOProviderConfig to map[string]SSOProviderConfig
• Replaced custom environment variable expansion with Viper's native binding mechanism using custom key delimiters
• Updated configuration file format and tests to reflect the new map-based structure

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
sso.yaml	Restructured providers from array to map format, sanitized example email address, and added quotes to client credentials
internal/config/sso.go	Changed Providers to map type, removed custom env expansion logic, added Viper key delimiter and env binding functions
internal/service/sso/service_test.go	Updated test fixtures to use map-based provider configuration

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[Copilot]

Returning a pointer to the loop variable v is problematic because the address of the loop variable remains the same across iterations. The returned pointer will point to the last value assigned to v after the loop completes, not the matched provider. Since Providers is now a map, you can directly return a pointer to the map value using &c.Providers[name] or use a different approach to safely return the provider.

Suggested change

	for _, v := range c.Providers {
	if v.Name == name {
	return &v
	}
	}
	if c == nil {
	return nil
	}
	if p, ok := c.Providers[name]; ok {
	return &p
	}