Add Phase 0 Quantum cast send seam (#1)

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## Motivation

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## Solution

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## PR Checklist

- [ ] Added Tests
- [ ] Added Documentation
- [ ] Breaking changes

Author: eacet

.gitignore

@@ -2,6 +2,7 @@
 /target*
 /*.sol
 CLAUDE.md
+/thoughts
 
 # Foundry artifacts
 out/