Add PKCE, token-body extras, AuthURL templating to OAuth2 → Add settings structs for Pattern-2 connector providers

- Add PKCE, token-body extras, AuthURL templating to OAuth2
- Add 13 connector provider enum values
- Add scopes, display names, name resolvers for 13 providers
- Add settings structs for Pattern-2 connector providers

Signed-off-by: Aurélien Sibiril <81782+aureliensibiril@users.noreply.github.com>

pkg/probodconfig/connector_config.go

@@ -35,6 +35,12 @@ type ConnectorConfig struct {
 type ConnectorConfigOAuth2 struct {
 	ClientID     string `json:"client-id"`
 	ClientSecret string `json:"client-secret"`
+	// IntegrationSlug is an operator-supplied value substituted into
+	// providers whose static AuthURL contains a "{integration_slug}"
+	// placeholder (Vercel-style integrations). It is propagated onto
+	// OAuth2Connector.AuthURLParams and resolved by
+	// connector.ApplyProviderDefaults.
+	IntegrationSlug string `json:"integration-slug,omitempty"`
 }
 
 func (c *Config) GetSlackSigningSecret() string {
@@ -89,6 +95,12 @@ func (c *ConnectorConfig) UnmarshalJSON(data []byte) error {
 			ClientSecret: config.ClientSecret,
 		}
 
+		if config.IntegrationSlug != "" {
+			oauth2Connector.AuthURLParams = map[string]string{
+				"integration_slug": config.IntegrationSlug,
+			}
+		}
+
 		c.Config = &oauth2Connector
 	default:
 		return fmt.Errorf("unknown connector protocol: %q", c.Protocol)