Remove file extension from media name used as alt text fallback.

Problem/Motivation

When syncing or embedding media assets from Acquia DAM, the module utilizes the asset's file name as a fallback string for the alt text attribute when an explicit alternative text is not provided.
Currently, this fallback includes the raw file extension (e.g., image-name.jpg or company-logo.png). It looks unpolished in the user interface if an image fails to load.

Steps to reproduce

• Configure and sync an image asset from Acquia DAM that does not have an explicitly defined metadata description or alternative text.
• Render the media asset in a Drupal view, field, or layout.
• Inspect the HTML markup.
• Expected result: The fallback alt text uses a clean media name without a file extension (e.g., alt="company-logo").
• Actual result: The fallback alt text includes the raw file extension (e.g., alt="company-logo.png").

Proposed resolution

Modify the media name fallback logic within the module to strip the file extension using a sanitization path helper or regular expression before setting it as the alt text fallback attribute.