feat(operator): inline edit mode on /partners/[slug]

Toggle the partner detail cards from read-only to editable in place. Edit
button in the PageHeader flips to Cancel + Save changes; cards expose
text inputs for name/domain/contact/billing, a 4-option segmented
control for status, and a 0–100 range slider for marginPct. Save sends
a PATCH diff (only fields that actually changed), refreshes the page
data, and exits edit mode. Cancel with unsaved changes confirms first.

Also tightens audit metadata: previously `Object.keys(dto)` on the
ValidationPipe-instantiated DTO listed every @IsOptional() field, even
when the request body didn't touch them. The partner.updated audit
event now records only the keys the operator actually sent.

services/platform-api/src/partners/partners.service.ts

@@ -92,7 +92,16 @@ export class PartnersService {
         resourceId: String(partner._id),
         resourceName: partner.name,
         partnerSlug: partner.slug,
-        metadata: { changes: Object.keys(dto as Record<string, unknown>) },
+        metadata: {
+          // class-validator's ValidationPipe(transform: true) instantiates the
+          // DTO with every @IsOptional() property defined (set to undefined
+          // when absent from the body). Filtering keeps the audit log honest —
+          // `changes` reflects what the operator actually sent, not the DTO
+          // shape.
+          changes: Object.keys(dto as Record<string, unknown>).filter(
+            (k) => (dto as Record<string, unknown>)[k] !== undefined,
+          ),
+        },
       },
       actor,
     )