Switch AuthorizationAttributes to batch and add AuthorizeBatch

Change AuthorizationAttributer.AuthorizationAttributes to take a slice
of resource ids and return policy.AttributesByID, so a single SQL
round-trip can load condition attributes for a whole batch. All
coredata implementations are migrated to a single
`WHERE id = ANY(@resource_ids::text[])` query that returns only the
rows it finds.

Authorizer gains:
  - AuthorizeBatch — all-or-nothing across a homogeneous (same entity
    type, same organization) resource set; rejects mixed entity types,
    mixed organizations, and empty batches with structured errors.
  - AuthorizeMulti — heterogeneous evaluation that returns one error
    per item and writes audit log entries in a single bulk insert.

The single-resource Authorize is rewired to delegate to AuthorizeBatch
so all paths share the same condition evaluation and audit logging.
recordAuditLog is split into buildAuditLogEntry plus a batch insert.

Tests cover the new batch and multi paths, mixed/empty/unsupported
resource cases, audit log batching, and dry-run behaviour.

Signed-off-by: Bryan Frimin <bryan@probo.com>

pkg/coredata/invitation.go

@@ -24,6 +24,7 @@ import (
 	"github.com/jackc/pgx/v5"
 	"go.gearno.de/kit/pg"
 	"go.probo.inc/probo/pkg/gid"
+	"go.probo.inc/probo/pkg/iam/policy"
 	"go.probo.inc/probo/pkg/page"
 )
 
@@ -142,34 +143,56 @@ WHERE
 
 // AuthorizationAttributes loads the minimal authorization attributes for policy condition evaluation.
 // It is intentionally lightweight and does not populate the Invitation struct.
-func (i *Invitation) AuthorizationAttributes(ctx context.Context, conn pg.Querier) (map[string]string, error) {
+func (i *Invitation) AuthorizationAttributes(
+	ctx context.Context,
+	conn pg.Querier,
+	resourceIDs []gid.GID,
+) (policy.AttributesByID, error) {
 	q := `
 SELECT
-    email, organization_id
+    id,
+    email,
+    organization_id
 FROM
     iam_invitations
 WHERE
-    id = $1
-LIMIT 1;
+    id = ANY(@resource_ids::text[])
 `
 
-	var (
-		email          string
-		organizationID gid.GID
-	)
-
-	if err := conn.QueryRow(ctx, q, i.ID).Scan(&email, &organizationID); err != nil {
-		if errors.Is(err, pgx.ErrNoRows) {
-			return nil, ErrResourceNotFound
-		}
-
-		return nil, fmt.Errorf("cannot query invitation iam attributes: %w", err)
+	args := pgx.StrictNamedArgs{
+		"resource_ids": resourceIDs,
 	}
 
-	return map[string]string{
-		"email":           email,
-		"organization_id": organizationID.String(),
-	}, nil
+	rows, err := conn.Query(ctx, q, args)
+	if err != nil {
+		return nil, fmt.Errorf("cannot query invitation authorization attributes: %w", err)
+	}
+	defer rows.Close()
+
+	attrsByID := make(policy.AttributesByID, len(resourceIDs))
+	for rows.Next() {
+		var (
+			id             gid.GID
+			email          string
+			organizationID gid.GID
+		)
+
+		err = rows.Scan(&id, &email, &organizationID)
+		if err != nil {
+			return nil, fmt.Errorf("cannot scan invitation authorization attributes: %w", err)
+		}
+
+		attrsByID[id] = policy.Attributes{
+			"email":           email,
+			"organization_id": organizationID.String(),
+		}
+	}
+
+	if err = rows.Err(); err != nil {
+		return nil, fmt.Errorf("cannot iterate invitation authorization attributes: %w", err)
+	}
+
+	return attrsByID, nil
 }
 
 func (i *Invitation) Update(ctx context.Context, conn pg.Tx, scope Scoper) error {