docs(architecture): baseline current design (#109)

Capture the brownfield architecture and its relationship to the project vision.\n\n- add the current-state SAD and five retrospective ADRs\n- classify vision vectors against implementation evidence\n- record requirements, risks, gates, and construction handoff

.aiwg/requirements/UC-003.md

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+# UC-003 — Operate Through Supported Surfaces
+
+**Primary actor:** Operator or integrating client  
+**Goal:** Start and inspect capabilities through CLI, War Room/HTTP, library, or MCP.
+
+## Main Flow
+
+1. User selects an entry surface.
+2. Surface validates and translates input into shared domain operations.
+3. Shared mission, target, arsenal, and reporting services execute.
+4. Results return in surface-appropriate form.
+
+**Implementation coverage:** `src/cli.ts`, `src/server.ts`, `src/index.ts`, `src/mcp-server.ts`, `src/ui/`.