Add bid parameters for Contxtful bid adapter and document Prebid Server support (#6181)

* Update contxtful.md to enable PBS support

* Add bid parameters section to Contxtful documentation

* Remove unnecessary blank line in Contxtful documentation

* Update Contxtful documentation to clarify required parameters

* chore: make customerId required

* docs: add config section

* docs: add section First Party Data

* docs: add AdUnit Format client side

* docs: add missing line break in First Party Data section of Contxtful documentation

* docs: update User Sync section in Contxtful documentation to clarify bidder filter settings

* docs: document "all"

* docs: remove redundant blank line in Contxtful documentation

Author: sebhtml

dev-docs/bidders/contxtful.md

@@ -13,7 +13,7 @@ safeframes_ok: true
 floors_supported: true
 fpd_supported: true 
 pbjs: true
-pbs: false
+pbs: true
 pbs_app_supported: false
 prebid_member: true
 multiformar_supported: will-bid-on-any
@@ -24,8 +24,80 @@ ortb_blocking_supported: true
 
 The Contxtful bidder adapter requires some setup. Contact us at [contact@contxtful.com](mailto:contact@contxtful.com)
 
+### Bid Params
+
+{: .table .table-bordered .table-striped }
+| Name        | Scope    | Description                                                | Example                      | Type                 |
+|-------------|----------|------------------------------------------------------------|------------------------------|----------------------|
+| `placementId`      | required | The placement identifier                                          | `'p12345678'` | `string`             |
+| `customerId`      | required | The customer identifier              | `'DEMO123456'`       | `string`           |
+
+### Configuration
+
+```javascript
+pbjs.setConfig({
+   "contxtful":{
+      "version":"v1",
+      "customer":"<<CUSTOMER_ID_HERE>>"
+   },
+   "realTimeData":{
+      "dataProviders":[
+         {
+            "name":"contxtful",
+            "waitForIt":true,
+            "params":{
+               "version":"v1",
+               "customer":"<<CUSTOMER_ID_HERE>>",
+               "bidders":[
+                  "contxtful"
+               ],
+               "adServerTargeting":true
+            }
+         }
+      ]
+   }
+}
+);
+```
+
+### First Party Data
+
+Publishers should use the `ortb2` method of setting First Party Data. The following fields are supported:
+
+- `ortb2.site.*`
+- `ortb2.user.*`
+- `ortb2.device.*`
+
+AdUnit-specific data is supported using `AdUnit.ortb2Imp.ext.*`
+
+### AdUnit Format client side
+
+```javascript
+ var adUnitList = [
+  {
+    code: 'AD_UNIT_NAME_HERE',
+    mediaTypes: { /* "<< ENTER_FORMAT_HERE >> */ },
+    bids: [{
+      bidder: 'contxtful',
+      params: {
+        placementId: "<<PLACEMENT_ID_HERE>>",
+        customerId: "<<CUSTOMER_ID_HERE>>"
+      }
+    }],
+    ortb2Imp: {
+      ext: {
+        data: {
+          divId: "<<EACH_AD_UNIT_DIV_ID>>"
+        }
+      }
+    }
+  }
+]
+```
+
 ### User Sync
-Contxtful recommends enabling [User Syncing](https://docs.prebid.org/dev-docs/publisher-api-reference/setConfig.html#setConfig-Configure-User-Syncing) to optimize match rate and monetization.
+
+Contxtful recommends enabling [User Syncing](https://docs.prebid.org/dev-docs/publisher-api-reference/setConfig#setConfig-Configure-User-Syncing) to optimize match rate and monetization.
 
 {% include dev-docs/storageAllowed.md %}
 
@@ -35,7 +107,7 @@ pbjs.setConfig({
   userSync: {
     filterSettings: {
       iframe: {
-        bidders: ['contxtful'],
+        bidders: '*',   // '*' means all bidders
         filter: 'include'
       }
     }
@@ -49,3 +121,5 @@ pbjs.bidderSettings = {
   }
 }
 ```
+
+Note - the `userSync.filterSettings.all` field is mutually exclusive and cannot be combined with the `userSync.filterSettings.iframe`/`userSync.filterSettings.image` fields in the `userSync` config. If the fields are used together, this will be considered an invalid config and only image pixels will be permitted.