feat(client,setting): complete Phase 2 with partitioned client_follow_logs

- apps/client (11 models): Client, ClientContact, ClientRequirement,
  ClientSchoolPreference, ClientFollowLog (partitioned),
  ClientFollowLogAttachment, ClientViewing, ClientPropertyMatch,
  ClientStatusLog, ClientFavoriteFolder, ClientFolderItem
- apps/client/0002 RunSQL: PARTITION BY RANGE(created_at) for
  client_follow_logs + monthly partitions + default; triggers
  update_client_last_follow + update_client_viewing_progress;
  partial unique index on client_no WHERE deleted_at IS NULL
- apps/setting (4 models): LookupGroup, LookupItem, TenantSetting,
  FieldRequirementRule (tenant schema only per spec)

manage.py check green; all 9 Phase 2 apps complete.

apps/client/models/folders.py

@@ -0,0 +1,48 @@
+from django.db import models
+
+from core.models.base import UUIDPrimaryKeyModel
+
+
+class ClientFavoriteFolder(UUIDPrimaryKeyModel):
+    staff = models.ForeignKey(
+        "org.Staff", on_delete=models.CASCADE, related_name="favorite_folders"
+    )
+    name = models.CharField(max_length=10)
+    is_default = models.BooleanField(default=False)
+    sort_order = models.IntegerField(default=0)
+    created_at = models.DateTimeField(auto_now_add=True)
+    deleted_at = models.DateTimeField(null=True, blank=True)
+
+    class Meta:
+        db_table = "client_favorite_folders"
+        indexes = [
+            models.Index(fields=["staff"], name="idx_cff_staff"),
+        ]
+        constraints = [
+            models.UniqueConstraint(
+                fields=["staff"],
+                condition=models.Q(is_default=True, deleted_at__isnull=True),
+                name="uq_cff_default_per_staff",
+            ),
+        ]
+
+
+class ClientFolderItem(models.Model):
+    folder = models.ForeignKey(
+        ClientFavoriteFolder, on_delete=models.CASCADE, related_name="items"
+    )
+    client = models.ForeignKey(
+        "fonrey_client.Client", on_delete=models.CASCADE, related_name="folder_items"
+    )
+    added_at = models.DateTimeField(auto_now_add=True)
+
+    class Meta:
+        db_table = "client_folder_items"
+        constraints = [
+            models.UniqueConstraint(
+                fields=["folder", "client"], name="uq_cfi_folder_client"
+            ),
+        ]
+        indexes = [
+            models.Index(fields=["client"], name="idx_cfi_client"),
+        ]