docs: propose CIP-113 QuickTx and TxPlan API refinement

[satran004]

Summary

Adds an architecture decision record reviewing the CIP-113 API introduced by PR #653 and proposing a refinement path aligned with the QuickTx intent model.

The ADR covers:

• correctness and composition findings from the current implementation
• a generic QuickTx extension and intent-codec registry with no quicktx -> cip113 dependency
• true TxPlan/YAML compatibility through semantic CIP-113 intents
• build lifecycle hooks for aggregation, materialization, index finalization, and post-balance verification
• proposed Java and YAML APIs
• service, backend, deployment-versioning, and cache boundaries
• staged implementation, review, qualification, and test plans

Purpose

This PR is intentionally documentation-only. It is intended to be the discussion space for API refinement before the CIP-113 public API is finalized.

Verification

• Markdown whitespace/diff validation completed
• No production or test code changed
• Branch is based directly on feat/basic-cip-113-integration at 6fc80337

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud