feat: IMAP mail sync with thread-to-contact matching (PRD §6.1)

Real IMAP connection via imapflow library:
- Connects to IMAP server (IMAPFlow, TLS on port 993)
- Fetches recent messages (configurable limit, default 20)
- Extracts: from, fromEmail, subject, date, snippet (200 chars)
- Thread-to-contact matching (PRD §6.1):
  1. Match sender email against persons table
  2. If no person match, extract domain and match against company.website
  3. Returns matchedCompany + matchedPerson for each email
- Audit-logged (action: crm.mailsync:imap)
- Zod validated (host, port, user, password, folder, limit)
- 502 on IMAP connection failure with detail
- 400 on validation failure

Tested: invalid creds → 502 'IMAP connection failed', missing host → 400

skills/design/design-templates/social-card-swiss/SKILL.md

@@ -0,0 +1,75 @@
+---
+name: social-card-swiss
+description: Swiss 网格 / 系统派社交卡 — 精确 / 系统化 / 技术感 / 方法论调性。卡角色含 system 封面 / numbered method / 对比 before-after / KPI tower / 横条 mini-chart / 截图解释 / 证据墙 / 收尾 checklist。用于 framework / checklist / 工具说明 / AI workflow / 产品更新 / KPI 总结。触发："做个方法卡 / 框架卡 / 工具拆解卡 / AI 工具卡 / 系统派结构卡"。NOT 情绪 / 文学 / 图主导卡，NOT 软生活 pastel 风。
+visibility: public
+mode: template
+carrier: fixed-image
+scenario: social-content
+pattern_source: pattern.html
+source_priority: skill-first
+triggers:
+  - "做个方法卡"
+  - "框架卡"
+  - "工具拆解卡"
+  - "AI 工具卡"
+  - "系统派卡"
+  - "结构化知识卡"
+  - "Swiss 网格卡"
+related_patterns: social-card-data-kpi, social-card-screenshot-explainer
+---
+
+# Social Card Swiss Template
+
+Use this template for structured social cards that should feel precise, systematic, technical, or method-driven.
+
+## Use When
+
+- The content is a framework, checklist, comparison, tool explanation, AI workflow, product update, KPI summary, or screenshot explainer.
+- The design should use grid, numbering, labels, metrics, or modular blocks.
+- The user wants a clean modern card that feels designed but not decorative.
+
+## Avoid When
+
+- The content is emotional, literary, image-led, or slow editorial.
+- The user wants a soft lifestyle/pastel look.
+- A plain poster or deck slide is a better fit than a social card.
+
+## Required Reading
+
+Read this `SKILL.md` first. Do **not** read `pattern.html` by default.
+
+Read `pattern.html` only if the selected card needs layout relationships that are hard to infer from this file. Extract only grid rhythm, component relationships, responsive/card behavior, and section hierarchy.
+
+## Design Strategy
+
+Choose a card role before choosing visual detail:
+
+- system cover
+- numbered method
+- comparison / before-after
+- KPI tower
+- horizontal bar / mini chart
+- screenshot explainer
+- evidence wall
+- closing checklist
+
+## Layout Bias
+
+Prefer:
+
+- strict grid and alignment
+- numbering systems and small metadata labels
+- clear typographic hierarchy
+- compact but readable card sections
+- data blocks, comparison rows, and interface frames
+
+Avoid:
+
+- random stickers, emoji icons, and decorative blobs
+- unclear focal hierarchy
+- screenshots too small to read
+- generic SaaS feature-card layouts
+
+## Platform / Size
+
+Use `canvas-and-device.md` for platform dimensions and export ratios. This template supplies structure, not fixed size.