return to Fleet after editing a PC opened from Fleet

Editing or retiring a PC launched from the Fleet view returned focus to the PCs list instead of Fleet. Fleet now tags its PC navigation with from=fleet, and PC Details and the edit form honor that origin for Back, Edit, Cancel, Save, and Retire. Absent the marker, every path still falls back to the PCs list.

plugins/computers/frontend/views/PCForm.vue

@@ -353,7 +353,7 @@
           <button type="submit" class="btn btn-primary" :disabled="saving">
             {{ saving ? 'Saving...' : 'Save PC' }}
           </button>
-          <router-link to="/pcs" class="btn btn-secondary">Cancel</router-link>
+          <router-link :to="returnTo" class="btn btn-secondary">Cancel</router-link>
         </div>
       </form>
     </div>
@@ -385,6 +385,11 @@ const router = useRouter()
 
 const isEdit = computed(() => !!route.params.id)
 
+// Return-navigation origin, threaded through from Fleet via ?from=fleet so
+// Cancel and a successful Save land back on Fleet; every other entry path
+// falls back to the PCs list.
+const returnTo = computed(() => (route.query.from === 'fleet' ? '/endpoints' : '/pcs'))
+
 // Seeded asset-type id for computers (see /api/assets/types). Custom-field
 // values are keyed by the underlying asset id, captured on load / create.
 const COMPUTER_ASSETTYPEID = 2
@@ -685,7 +690,7 @@ async function savePC() {
       }
     }
 
-    router.push('/pcs')
+    router.push(returnTo.value)
   } catch (err) {
     console.error('Error saving PC:', err)
     error.value = apiError(err, 'Failed to save PC')