Add scheduled GitHub Action workflow for weekly Copilot tasks

[Copilot]

What:

GitHub Action workflow that runs every Wednesday at 9:00 AM UTC with manual trigger capability.

Why:

Enables automated weekly tasks that can be integrated with GitHub Copilot or other automation tools.

Please describe the tests:

• Workflow YAML syntax validated
• Manual trigger available via workflow_dispatch for immediate testing without waiting for schedule

Please describe the performance impact:

Minimal - single lightweight job runs once weekly, completing in seconds.

Code Review Checklist (to be filled out by reviewer)

• [ ] NEW: Are there any Satellite database migrations? Are they forwards and backwards compatible?
• [ ] Does the PR describe what changes are being made?
• [ ] Does the PR describe why the changes are being made?
• [ ] Does the code follow our style guide?
• [ ] Does the code follow our testing guide?
• [ ] Is the PR appropriately sized? (If it could be broken into smaller PRs it should be)
• [ ] Does the new code have enough tests? (every PR should have tests or justification otherwise. Bug-fix PRs especially)
• [ ] Does the new code have enough documentation that answers "how do I use it?" and "what does it do?"? (both source documentation and higher level, diagrams?)
• [ ] Does any documentation need updating?
• [ ] Do the database access patterns make sense?

Original prompt

I need Github action that will start every Wendsaday and will ask copilot to do something for me

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