feat(edge-app-template): add categories to manifest files

- Add categories field to screenly.yml and screenly_qc.yml
- Update create-an-edge-app skill to remind updating categories

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: nicomiguelino

.claude/skills/create-an-edge-app/SKILL.md

@@ -31,6 +31,7 @@ All apps depend on the `@screenly/edge-apps` library (`workspace:../edge-apps-li
 
 ### About the Manifest Files
 
+- Update the `categories` key to reflect the app's purpose.
 - Add any app-specific settings under the `settings` key, sorted alphabetically.
 - More information about manifest files can be found in the [Edge Apps documentation in the `Screenly/cli` repository](https://raw.githubusercontent.com/Screenly/cli/refs/heads/master/docs/EdgeApps.md).
 

edge-apps/.bun-create/edge-app-template/screenly.yml

@@ -3,6 +3,8 @@ syntax: manifest_v1
 description: {{APP_DESCRIPTION}}
 icon: https://playground.srly.io/edge-apps/{{APP_NAME}}/static/img/icon.svg
 author: Screenly, Inc.
+categories:
+  - Messaging & Content
 ready_signal: true
 settings:
   display_errors:

edge-apps/.bun-create/edge-app-template/screenly_qc.yml

@@ -3,6 +3,8 @@ syntax: manifest_v1
 description: {{APP_DESCRIPTION}}
 icon: https://playground.srly.io/edge-apps/{{APP_NAME}}/static/img/icon.svg
 author: Screenly, Inc.
+categories:
+  - Messaging & Content
 ready_signal: true
 settings:
   display_errors: