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/experiment-suite/figure_examples/make_fig_03_heatmap.py

@@ -0,0 +1,43 @@
+"""Generate fig_03_method_x_dataset_heatmap.pdf — MSE heatmap across methods × datasets."""
+import os
+import matplotlib.pyplot as plt
+import seaborn as sns
+import numpy as np
+from style_kit import add_panel_label, add_simulated_watermark, apply_publication_style, save_publication_bundle
+
+apply_publication_style()
+
+datasets = ["ETTh1", "ETTh2", "ETTm1", "ETTm2", "ECL", "Traffic", "Weather"]
+methods = ["DLinear", "Informer", "Autoformer", "FEDformer",
+           "PatchTST", "iTrans.", "TimeMixer", "Ours"]
+
+mse = np.array([
+    [0.394, 0.495, 0.439, 0.411, 0.371, 0.364, 0.358, 0.355],
+    [0.310, 0.452, 0.388, 0.358, 0.301, 0.294, 0.290, 0.287],
+    [0.382, 0.512, 0.421, 0.401, 0.366, 0.359, 0.357, 0.354],
+    [0.279, 0.401, 0.336, 0.318, 0.262, 0.258, 0.254, 0.252],
+    [0.166, 0.219, 0.187, 0.179, 0.158, 0.151, 0.150, 0.149],
+    [0.434, 0.608, 0.545, 0.508, 0.412, 0.406, 0.405, 0.402],
+    [0.241, 0.318, 0.281, 0.265, 0.227, 0.224, 0.223, 0.220],
+])
+
+fig, ax = plt.subplots(figsize=(6.4, 3.4))
+sns.heatmap(
+    mse, annot=True, fmt=".3f",
+    xticklabels=methods, yticklabels=datasets,
+    cmap="RdYlGn_r",
+    cbar_kws={"label": "MSE", "shrink": 0.7, "pad": 0.02},
+    annot_kws={"size": 7.5},
+    linewidths=0.4, linecolor="white",
+    ax=ax,
+)
+ax.set_xticklabels(ax.get_xticklabels(), rotation=30, ha="right")
+ax.set_yticklabels(ax.get_yticklabels(), rotation=0)
+add_panel_label(ax, "(b)")
+add_simulated_watermark(ax, y=-0.16)
+
+plt.tight_layout(pad=0.4)
+out = os.path.join(os.path.dirname(os.path.abspath(__file__)), "fig_03_method_x_dataset_heatmap")
+save_publication_bundle(fig, out)
+plt.close(fig)
+print(f"Wrote {out}.pdf/.svg/.tiff")