[Custom Branding] Update text (#151631)

## Summary

This PR updates text for Custom Branding.
<img width="1505" alt="Screenshot 2023-02-20 at 16 22 10"
src="https://user-images.githubusercontent.com/1937956/220145333-68aedb04-5c57-4dca-aa1f-037a245100ba.png">



### Checklist

Delete any items that are not applicable to this PR.

- [X] Any text added follows [EUI's writing
guidelines](https://elastic.github.io/eui/#/guidelines/writing), uses
sentence case text and includes [i18n
support](https://github.com/elastic/kibana/blob/main/packages/kbn-i18n/README.md)
- [X]
[Documentation](https://www.elastic.co/guide/en/kibana/master/development-documentation.html)
was added for features that require explanation or tutorials
~- [ ] [Unit or functional
tests](https://www.elastic.co/guide/en/kibana/master/development-tests.html)
were updated or added to match the most common scenarios~
~- [ ] Any UI touched in this PR is usable by keyboard only (learn more
about [keyboard
accessibility](https://webaim.org/techniques/keyboard/))~
~- [ ] Any UI touched in this PR does not create any new axe failures
(run axe in browser:
[FF](https://addons.mozilla.org/en-US/firefox/addon/axe-devtools/),
[Chrome](https://chrome.google.com/webstore/detail/axe-web-accessibility-tes/lhdoppojpmngadmnindnejefpokejbdd?hl=en-US))~
~- [ ] If a plugin configuration key changed, check if it needs to be
allowlisted in the cloud and added to the [docker
list](https://github.com/elastic/kibana/blob/main/src/dev/build/tasks/os_packages/docker_generator/resources/base/bin/kibana-docker)~
~- [ ] This renders correctly on smaller devices using a responsive
layout. (You can test this [in your
browser](https://www.browserstack.com/guide/responsive-testing-on-local-server))~
~- [ ] This was checked for [cross-browser
compatibility](https://www.elastic.co/support/matrix#matrix_browsers)~


### For maintainers

- [ ] This was checked for breaking API changes and was [labeled
appropriately](https://www.elastic.co/guide/en/kibana/master/contributing.html#kibana-release-notes-process)

---------

Co-authored-by: kibanamachine <42973632+kibanamachine@users.noreply.github.com>
Co-authored-by: Vadim Kibana <82822460+vadimkibana@users.noreply.github.com>

docs/developer/plugin-list.asciidoc

@@ -488,7 +488,7 @@ The plugin exposes the static DefaultEditorController class to consume.
 
 |{kib-repo}blob/{branch}/x-pack/plugins/custom_branding/README.md[customBranding]
 |This is a plugin to configure custom branding.
-This plugin is currently under active development; do not use.
+Plugin server-side only. Plugin has three main functions:
 
 
 |<<dashboard-enhanced-plugin>>

x-pack/plugins/custom_branding/README.md

@@ -1,10 +1,21 @@
 # customBranding
-## !! UNDER DEVELOPMENT !!
 This is a plugin to configure custom branding.
-This plugin is currently under active development; do not use.
+Plugin server-side only. Plugin has three main functions:
+1. To check license (custom branding is available for enterprise licenses and above)
+2. To register itself with a custom branding service
+3. To register UI settings
+
+Properties that can be configured through custom branding are:
+1. Custom logo (replaces the default `Elastic` logo in the chrome header and on the login page)
+2. Customized text (replaces the `elastic` logo in the the chrome header)
+3. Page title
+4. Favicons - PNG and SVG
 
 ---
 
 ## Development
 
+For detailed architectural overview, see image: ![architecture_diagram](./architecture_diagram.png)
+
+
 See the [kibana contributing guide](https://github.com/elastic/kibana/blob/main/CONTRIBUTING.md) for instructions setting up your development environment.

x-pack/plugins/custom_branding/server/plugin.ts

@@ -96,7 +96,6 @@ export class CustomBrandingPlugin implements Plugin {
       const key = settingsKeys[i];
       const fullKey = `xpackCustomBranding:${key}`;
       const value = await uiSettingsClient.get(fullKey);
-      this.logger.info(`Fetching custom branding key ${fullKey} with value ${value}`);
       if (value) {
         branding[key] = value;
       }

x-pack/plugins/custom_branding/server/ui_settings.ts

@@ -15,7 +15,7 @@ export const UI_SETTINGS_CUSTOMIZED_LOGO = 'xpackCustomBranding:customizedLogo';
 export const UI_SETTINGS_PAGE_TITLE = 'xpackCustomBranding:pageTitle';
 export const UI_SETTINGS_FAVICON_PNG = 'xpackCustomBranding:faviconPNG';
 export const UI_SETTINGS_FAVICON_SVG = 'xpackCustomBranding:faviconSVG';
-export const PLUGIN_ID = 'Custom Branding';
+export const PLUGIN_ID = 'Custom branding';
 
 const kbToBase64Length = (kb: number) => Math.floor((kb * 1024 * 8) / 6);
 const maxLogoSizeInBase64 = kbToBase64Length(200);
@@ -59,15 +59,16 @@ const subscriptionLink = `
         })}
       </a>
   `;
+
 export function registerUiSettings(core: CoreSetup<object, unknown>) {
   core.uiSettings.registerGlobal({
     [UI_SETTINGS_CUSTOM_LOGO]: {
       name: i18n.translate('xpack.customBranding.customLogoLabel', {
-        defaultMessage: 'Logo icon',
+        defaultMessage: 'Custom logo',
       }),
       value: null,
       description: i18n.translate('xpack.customBranding.customLogoDescription', {
-        defaultMessage: `Replaces the Elastic logo.  Logos look best when they are no larger than 128 x 128 pixels and have a transparent background. {subscriptionLink}`,
+        defaultMessage: `Replaces the Elastic logo. Logos look best when they are no larger than 128 x 128 pixels and have a transparent background. {subscriptionLink}`,
         values: { subscriptionLink },
       }),
       sensitive: true,
@@ -83,7 +84,7 @@ export function registerUiSettings(core: CoreSetup<object, unknown>) {
       }),
       value: null,
       description: i18n.translate('xpack.customBranding.customizedLogoDescription', {
-        defaultMessage: `Replaces the Elastic text. Images look best when they are no larger than 200 x 84 pixels and have a transparent background. {subscriptionLink}`,
+        defaultMessage: `Replaces the text next to the logo. Images look best when they are no larger than 200 x 84 pixels and have a transparent background. {subscriptionLink}`,
         values: { subscriptionLink },
       }),
       sensitive: true,
@@ -115,7 +116,7 @@ export function registerUiSettings(core: CoreSetup<object, unknown>) {
       }),
       value: null,
       description: i18n.translate('xpack.customBranding.faviconSVGDescription', {
-        defaultMessage: `A link to an icon that will appear on browser tabs. Recommended size is 16 x 16 pixels.  {subscriptionLink}`,
+        defaultMessage: `The URL of an image that will appear on browser tabs. Recommended size is 16 x 16 pixels. {subscriptionLink}`,
         values: { subscriptionLink },
       }),
       sensitive: true,
@@ -131,7 +132,7 @@ export function registerUiSettings(core: CoreSetup<object, unknown>) {
       }),
       value: null,
       description: i18n.translate('xpack.customBranding.faviconPNGDescription', {
-        defaultMessage: `An icon for use in browsers that don’t support svg.  {subscriptionLink}`,
+        defaultMessage: `The URL of an image for use in browsers that don’t support SVG. {subscriptionLink}`,
         values: { subscriptionLink },
       }),
       sensitive: true,