feat: Document completed tasks for KMS, Cryptography, and Plugin Libraries

- Added detailed task completion records for KMS interface implementation and CLI support for file-based keys.
- Documented security enhancements including Argon2id password hashing, audit event contracts, and rate limiting configurations.
- Included scoped service support and integration updates for the Plugin platform, ensuring proper DI handling and testing coverage.

docs/technical/README.md

@@ -0,0 +1,17 @@
+# Technical Documentation Index
+
+> Use this hub when you need the full implementation detail: architecture blueprints, data contracts, developer guides, and operations playbooks. Each section below links to the canonical sources already living in `docs/**`.
+
+## Sections
+- [Strategy & Core Specs](strategy/README.md)
+- [Platform Architecture & Module Dossiers](architecture/README.md)
+  - [Component map](architecture/component-map.md)
+- [Interfaces, Contracts & Schemas](interfaces/README.md)
+- [Development Guides & Tooling](development/README.md)
+- [Operations, Deployment & Offline](operations/README.md)
+- [Observability, Notifications & Telemetry](observability/README.md)
+- [Security, Risk & Governance](security/README.md)
+- [Process, Coordination & Change Logs](process/README.md)
+
+---
+Need a doc that is missing here? Raise an entry in `docs/TASKS.md` so the index stays complete.