Update description field guidance to 5 words instead of 1-2 sentences

- Changed description field guidance from '1-2 sentences' to '5 words'
- Updated YAML example to show concise 5-word description
- Addresses feedback from @mrubens in PR comment #3041823916

Author: roomote

src/core/prompts/instructions/create-mode.ts

@@ -26,7 +26,7 @@ If asked to create a project mode, create it in .roomodes in the workspace root.
   * groups: Array of allowed tool groups (can be empty). Each group can be specified either as a string (e.g., "edit" to allow editing any file) or with file restrictions (e.g., ["edit", { fileRegex: "\\.md$", description: "Markdown files only" }] to only allow editing markdown files)
 
 - The following fields are optional but highly recommended:
-  * description: A short, human-readable description of what this mode does (1-2 sentences)
+  * description: A short, human-readable description of what this mode does (5 words)
   * whenToUse: A clear description of when this mode should be selected and what types of tasks it's best suited for. This helps the Orchestrator mode make better decisions.
   * customInstructions: Additional instructions for how the mode should operate
 
@@ -37,7 +37,7 @@ Both files should follow this structure (in YAML format):
 customModes:
   - slug: designer  # Required: unique slug with lowercase letters, numbers, and hyphens
     name: Designer  # Required: mode display name
-    description: A UI/UX expert specializing in design systems and responsive frontend development.  # Optional but recommended: short description
+    description: UI/UX design systems expert  # Optional but recommended: short description (5 words)
     roleDefinition: >-
       You are Roo, a UI/UX expert specializing in design systems and frontend development. Your expertise includes:
       - Creating and maintaining design systems