Add CARA Confidential Audit & Regulatory Assistant Proposal

PR Title: Development Fund Proposal: CARA Compliance Assistant Proposal file: [cara-compliance-assistant.md] Summary CARA is a privacy-preserving regulatory compliance infrastructure layer for the Canton Network. It enables automated AML/KYC checks and real-time regulatory reporting while maintaining strict institutional data confidentiality through Daml’s sub-transaction privacy model. Checklist Proposal file added under /proposals/ Milestones and funding amounts defined Acceptance criteria included Alignment with Canton priorities described Notes for Reviewers This proposal specifically addresses the "Privacy Paradox" in institutional finance. Pay close attention to the CIAP (Cross-Institutional Attestation Protocol) in Milestone 2, which allows for zero-PII sharing between banks a key differentiator for the Canton ecosystem.