Submission UI Improvement

1. The status message on the submission status page should be rephrased to imply action from the user. Currently, while it's pending confirmation, the message is "Status: Validation completed without any error" on top and "INSERT PROCESSING" in the submission column. This doesn't imply action on the user. Suggest changing it to "Status: Validation completed without any error, pending submitter action" on top and "INSERT PENDING" in the status column if there are no errors.
2. On the Data Submission status page: "Viral Genomes: ##" should be replaced with "Samples: ##".
3. Add text into the submission status page to let the user know they can go back to the "new submissions" page and submit additional sequence data if needed.
4. For the Missing files dialog on the status page: Show a count of how many files are missing.

Start by locating the submission status page and its Missing files dialog, then compare the current status, submission-column, and Viral Genomes text with the issue. Update the four requested messages and add the missing-file count, the pending submitter action wording, and guidance for returning to new submissions; verify each state on the status page.

Written by the indexing model from the issue text.