first step towards having a centralized set of error sentinels that can be passed around corso instead of re-using low level error sentinels like those found in the graph/errors.go file.
This PR works as a standalone, and only handles the lowest hanging fruit. SDK consumers will need to change their error enum references, but all api behavior should remain the same.
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#### Does this PR need a docs update or release note?
- [x] ⛔ No
#### Type of change
- [x] 🤖 Supportability/Tests
#### Issue(s)
* #4685
#### Test Plan
- [x] ⚡ Unit test
- [x] 💚 E2E
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