fix(accessibility): add descriptive alt text to get started images v2

[Earnwithalee7890]

What changed? Why?

This PR improves accessibility across the Get Started documentation by adding or enhancing descriptive alt text for all images. This ensures users relying on screen readers and other assistive technologies can understand the visual content and its purpose within the documentation.

Files updated:

• Get Started documentation pages with image content improvements
• All alt text now provides meaningful, contextual descriptions rather than generic labels
• Descriptions focus on what the images show and their relevance to the surrounding content

The changes follow WCAG 2.1 accessibility guidelines to ensure the documentation is inclusive and accessible to all users, regardless of how they consume the content.

Notes to reviewers

• All alt text follows accessibility best practices
• Descriptions are concise but informative, providing sufficient context
• No changes to actual image files or documentation structure
• Only alt attributes have been updated
• All changes maintain proper MDX syntax

How has it been tested?

• Manually reviewed each alt text change for accuracy and clarity
• Verified all images render correctly with updated alt attributes
• Confirmed alt text provides meaningful information for screen reader users
• Validated that documentation builds successfully with no syntax errors
• Checked that visual presentation remains unchanged

[cb-heimdall]

🟡 Heimdall Review Status

Requirement	Status	More Info
Reviews	🟡 0/2	Denominator calculation Show calculation 1 if user is bot 0 1 if user is external 0 2 if repo is sensitive 0 From .codeflow.yml 1 Additional review requirements Show calculation Max 0 0 From CODEOWNERS 0 Global minimum 0 Max 1 1 1 if commit is unverified 1 Sum 2