feat(M2): Persönliche Dashboards — Tabelle, CRUD, Lazy-Seed, RLS (#360)

- dashboards-Tabelle (Layout JSONB, Tabs, is_default, partial unique name index)
- 6 CRUD-Endpoints /api/v1/dashboards, Owner-only (saved_views-Präzedenz), Audit
- Lazy Default-Seed aus MiniApp-Registry (permission-gefiltert, 12-Spalten-Flow)
- CORE_PERMISSIONS dashboard:read/write (fixt Phantom-Permission in dashboard.py)
- Migration 0144: RLS crm_api+crm_worker + konvergenter Fix der 3 Phase-L-Policies
- Tests: test_dashboards_backend.py 23/23 (TDD rot->grün); Regression 162/163

app/models/__init__.py

@@ -17,12 +17,13 @@ from app.models.contact_folder import ContactFolder
 from app.models.contact_merge import ContactMergeHistory
 from app.models.currency import Currency
 from app.models.custom_field_definition import CustomFieldDefinition
+from app.models.dashboard import Dashboard
 from app.models.entity_history import EntityHistory
 from app.models.entity_permission import EntityPermission
 from app.models.entity_policy import EntityPolicy
 from app.models.group import Group, UserGroup
 from app.models.notification import Notification, NotificationPreference, NotificationType
-from app.models.outbox import EventOutbox, OutboxDelivery
+from app.models.outbox import EventOutbox, OutboxDelivery  # noqa: F401
 from app.models.owned_mixin import OwnedMixin
 from app.models.permission_delegation import PermissionDelegation
 from app.models.permission_template import PermissionTemplate
@@ -80,6 +81,7 @@ __all__ = [
     "WorkflowInstance",
     "WorkflowStepHistory",
     "SavedView",
+    "Dashboard",
 ]
 from app.models.entity_attachment import EntityAttachment  # noqa: F401
 from app.models.workspace import (  # noqa: F401

app/models/dashboard.py

@@ -0,0 +1,52 @@
+"""Dashboard model — personal per-user dashboards (Phase M2).
+
+Dashboards are personal (user-owned) layouts of MiniApp instances: tabs,
+widget placements and per-instance settings, stored as JSONB. Access is
+owner-only (saved_views precedent) — the active workspace limits only the
+available widget types (Phase N), never this personal layout.
+"""
+
+from __future__ import annotations
+
+import uuid
+from typing import Any
+
+from sqlalchemy import Boolean, ForeignKey, Index, String, text
+from sqlalchemy.dialects.postgresql import JSONB
+from sqlalchemy.dialects.postgresql import UUID as PGUUID
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.core.db import Base, TenantMixin
+
+
+class Dashboard(Base, TenantMixin):
+    """Personal dashboard — per-user layout of MiniApp instances."""
+
+    __tablename__ = "dashboards"
+    __table_args__ = (
+        # Partial unique: soft-deleted dashboards free their name (unlike the
+        # saved_views plain constraint, which keeps names occupied forever).
+        Index(
+            "uq_dashboards_tenant_user_name",
+            "tenant_id",
+            "user_id",
+            "name",
+            unique=True,
+            postgresql_where=text("deleted_at IS NULL"),
+        ),
+        Index("ix_dashboards_tenant_user", "tenant_id", "user_id"),
+    )
+
+    id: Mapped[uuid.UUID] = mapped_column(
+        PGUUID(as_uuid=True), primary_key=True, default=uuid.uuid4
+    )
+    name: Mapped[str] = mapped_column(String(100), nullable=False)
+    # Layout JSONB (validated by app.schemas.dashboard.DashboardLayout):
+    # {version, tabs: [{id, name, widgets: [{app_id, settings, col, row, spans}]}]}
+    layout: Mapped[dict[str, Any]] = mapped_column(
+        JSONB, nullable=False, default=dict
+    )
+    is_default: Mapped[bool] = mapped_column(Boolean, nullable=False, default=False)
+    user_id: Mapped[uuid.UUID] = mapped_column(
+        PGUUID(as_uuid=True), ForeignKey("users.id", ondelete="CASCADE"), nullable=False
+    )