Add SendGrid access review driver

Implement a SendGrid access-review driver that fetches teammates
from the SendGrid API and maps them into AccountRecord values.

Register SendGrid as a connector provider, expose it through the
connector provider enum, and add a migration that extends the
connector_provider type with SENDGRID.

Cover the new driver with a VCR-backed fixture test and helper
tests for role and response-shape handling to keep parsing robust.

Signed-off-by: Cursor Agent <cursoragent@cursor.com>

Co-authored-by: Bryan FRIMIN <bryan@frimin.fr>

pkg/coredata/connector_provider.go

@@ -41,6 +41,7 @@ const (
 	ConnectorProviderGitHub       ConnectorProvider = "GITHUB"
 	ConnectorProviderIntercom     ConnectorProvider = "INTERCOM"
 	ConnectorProviderResend       ConnectorProvider = "RESEND"
+	ConnectorProviderSendGrid     ConnectorProvider = "SENDGRID"
 	ConnectorProviderMicrosoft365 ConnectorProvider = "MICROSOFT_365"
 	ConnectorProviderGitLab       ConnectorProvider = "GITLAB"
 	ConnectorProviderBitbucket    ConnectorProvider = "BITBUCKET"
@@ -84,6 +85,7 @@ func ConnectorProviders() []ConnectorProvider {
 		ConnectorProviderGitHub,
 		ConnectorProviderIntercom,
 		ConnectorProviderResend,
+		ConnectorProviderSendGrid,
 		ConnectorProviderMicrosoft365,
 		ConnectorProviderGitLab,
 		ConnectorProviderBitbucket,
@@ -123,6 +125,7 @@ func (v ConnectorProvider) IsValid() bool {
 		ConnectorProviderGitHub,
 		ConnectorProviderIntercom,
 		ConnectorProviderResend,
+		ConnectorProviderSendGrid,
 		ConnectorProviderMicrosoft365,
 		ConnectorProviderGitLab,
 		ConnectorProviderBitbucket,

pkg/coredata/migrations/20260529T065300Z.sql

@@ -0,0 +1,15 @@
+-- Copyright (c) 2026 Probo Inc <hello@getprobo.com>.
+--
+-- Permission to use, copy, modify, and/or distribute this software for any
+-- purpose with or without fee is hereby granted, provided that the above
+-- copyright notice and this permission notice appear in all copies.
+--
+-- THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+-- REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+-- AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+-- INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+-- LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+-- OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+-- PERFORMANCE OF THIS SOFTWARE.
+
+ALTER TYPE connector_provider ADD VALUE IF NOT EXISTS 'SENDGRID';