docs: expand .cards — vision, comparisons, business rationale, open questions

26 cards covering:
- Project philosophy (session isolation, process discipline, dissipative structure)
- Comparisons (vs skill, vs dynamic workflow)
- Business rationale (FTE vs vendor, OPC, switching cost)
- Learning model (memory + skill + workflow)
- Self-improvement (reflective workflow, eval)
- Open questions (workflow granularity, human-in-the-loop)

.cards/open-question-workflow-granularity.md

@@ -0,0 +1,20 @@
+---
+title: "Open Question — Workflow Granularity and Composition"
+created: "2026-06-07"
+source: "openclaw-xiaomo"
+tags: [architecture, open-question]
+category: "architecture"
+links:
+  - cognitive-process-orchestration
+  - skill-vs-workflow-different-layers
+  - domain-experts-own-the-process
+---
+
+**待讨论。**
+
+Workflow 的粒度问题：solve-issue 是端到端的大 workflow（planner → developer → reviewer → tester → committer），但现实中有些场景只需要管一个环节（比如只用 uwf 管 code review，其他部分用 skill 或手动）。
+
+问题：
+- Workflow 是否应该支持嵌套或组合——小 workflow 作为大 workflow 的一个 role？
+- 还是粒度完全由用户自己决定，引擎不需要管？
+- 组合式 workflow 和单体 workflow 各自的 trade-off 是什么？