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/core.py

@@ -0,0 +1,147 @@
+from django.contrib.postgres.fields import ArrayField
+from django.db import models
+
+from core.enums import (
+    ClientActivityLevel,
+    ClientBuyingPurpose,
+    ClientGrade,
+    ClientIdType,
+    ClientInvalidReason,
+    ClientPaymentMethod,
+    ClientPropertiesOwned,
+    ClientPropertyUsage,
+    ClientStatus,
+    ClientTransactedPropertyType,
+    ClientTransactedType,
+    ClientTransferToPublicType,
+    ClientType,
+)
+from core.models.base import AuditedModel
+
+
+class Client(AuditedModel):
+    client_no = models.CharField(max_length=30, unique=True)
+    client_type = models.CharField(
+        max_length=20, choices=ClientType.choices, default=ClientType.PRIVATE
+    )
+    status = models.CharField(
+        max_length=20, choices=ClientStatus.choices, default=ClientStatus.BUYING
+    )
+    grade = models.CharField(
+        max_length=5, choices=ClientGrade.choices, default=ClientGrade.C
+    )
+    property_usage = models.CharField(
+        max_length=30,
+        choices=ClientPropertyUsage.choices,
+        default=ClientPropertyUsage.RESIDENTIAL,
+    )
+    buying_purpose = ArrayField(
+        models.CharField(max_length=20, choices=ClientBuyingPurpose.choices),
+        blank=True,
+        default=list,
+    )
+    payment_method = models.CharField(
+        max_length=30, choices=ClientPaymentMethod.choices, blank=True, default=""
+    )
+    properties_owned = models.CharField(
+        max_length=20, choices=ClientPropertiesOwned.choices, blank=True, default=""
+    )
+    has_loan_record = models.BooleanField(null=True, blank=True)
+
+    id_type = models.CharField(
+        max_length=20, choices=ClientIdType.choices, blank=True, default=""
+    )
+    id_number_enc = models.BinaryField(null=True, blank=True)
+
+    source = models.CharField(max_length=50, blank=True, default="")
+    remarks = models.TextField(blank=True, default="")
+
+    is_starred = models.BooleanField(default=False)
+    is_pinned = models.BooleanField(default=False)
+    is_big_value = models.BooleanField(default=False)
+    is_protected = models.BooleanField(default=False)
+    prefers_new_house = models.BooleanField(null=True, blank=True)
+
+    transfer_to_public_type = models.CharField(
+        max_length=20,
+        choices=ClientTransferToPublicType.choices,
+        blank=True,
+        default="",
+    )
+    transferred_public_at = models.DateTimeField(null=True, blank=True)
+
+    invalid_reason = models.CharField(
+        max_length=30, choices=ClientInvalidReason.choices, blank=True, default=""
+    )
+    invalidated_at = models.DateTimeField(null=True, blank=True)
+
+    transacted_at = models.DateField(null=True, blank=True)
+    transacted_property = models.ForeignKey(
+        "fonrey_property.Property",
+        null=True,
+        blank=True,
+        on_delete=models.SET_NULL,
+        related_name="transacted_clients",
+    )
+    transacted_price = models.DecimalField(
+        max_digits=12, decimal_places=2, null=True, blank=True
+    )
+    transacted_type = models.CharField(
+        max_length=20, choices=ClientTransactedType.choices, blank=True, default=""
+    )
+    transacted_property_type = models.CharField(
+        max_length=20,
+        choices=ClientTransactedPropertyType.choices,
+        blank=True,
+        default="",
+    )
+
+    first_recorder = models.ForeignKey(
+        "org.Staff",
+        null=True,
+        blank=True,
+        on_delete=models.SET_NULL,
+        related_name="first_recorded_clients",
+    )
+    owner = models.ForeignKey(
+        "org.Staff",
+        null=True,
+        blank=True,
+        on_delete=models.SET_NULL,
+        related_name="owned_clients",
+    )
+    org_unit = models.ForeignKey(
+        "org.OrgUnit",
+        null=True,
+        blank=True,
+        on_delete=models.SET_NULL,
+        related_name="clients",
+    )
+
+    activity_level = models.CharField(
+        max_length=20, choices=ClientActivityLevel.choices, blank=True, default=""
+    )
+    last_active_at = models.DateTimeField(null=True, blank=True)
+    last_follow_at = models.DateTimeField(null=True, blank=True)
+
+    commission_date = models.DateField(null=True, blank=True)
+    entrust_count = models.SmallIntegerField(default=1)
+
+    version = models.IntegerField(default=1)
+
+    class Meta:
+        db_table = "clients"
+        indexes = [
+            models.Index(fields=["client_type", "status"], name="idx_clients_type_stat"),
+            models.Index(fields=["owner"], name="idx_clients_owner"),
+            models.Index(fields=["org_unit"], name="idx_clients_org_unit"),
+            models.Index(
+                fields=["activity_level", "-last_active_at"],
+                name="idx_clients_activity",
+            ),
+            models.Index(fields=["grade"], name="idx_clients_grade"),
+            models.Index(
+                fields=["-transferred_public_at"], name="idx_clients_transferred"
+            ),
+            models.Index(fields=["-last_follow_at"], name="idx_clients_last_follow"),
+        ]