Updating TPRM flow, adding encoded URLs, material change guidance, formatting

Why is this change being made?

Source: weekly sync (flow chart and material change guidance). Flowchart for TPRM needed to be updated based on our current process. Also made a few more tweaks:

1. Updating URLs for creating issues to use template for efficiency
2. Added guidance for reviewing vendors within 12 month window for transparency
3. Attempt to Stack footnotes for visibility
4. Combine Yellow/Green rows for tightness

Author Checklist

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