Add audit start and end dates to audits

ISO audits often span a window distinct from certificate validity.
Store optional audit_start_date and audit_end_date on the audit
record and expose them through GraphQL, MCP, CLI, n8n, and console.

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

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

pkg/server/api/mcp/v1/specification.yaml

@@ -4674,6 +4674,18 @@ components:
             - "null"
           format: date-time
           description: Valid until date
+        audit_start_date:
+          type:
+            - string
+            - "null"
+          format: date-time
+          description: Audit start date
+        audit_end_date:
+          type:
+            - string
+            - "null"
+          format: date-time
+          description: Audit end date
         state:
           $ref: "#/components/schemas/AuditState"
           description: Audit state
@@ -4791,6 +4803,14 @@ components:
           type: string
           format: date-time
           description: Valid until date
+        audit_start_date:
+          type: string
+          format: date-time
+          description: Audit start date
+        audit_end_date:
+          type: string
+          format: date-time
+          description: Audit end date
         state:
           $ref: "#/components/schemas/AuditState"
           description: Audit state
@@ -4827,6 +4847,18 @@ components:
             - "null"
           format: date-time
           description: Valid until date
+        audit_start_date:
+          type:
+            - string
+            - "null"
+          format: date-time
+          description: Audit start date
+        audit_end_date:
+          type:
+            - string
+            - "null"
+          format: date-time
+          description: Audit end date
         state:
           anyOf:
             - $ref: "#/components/schemas/AuditState"