feat(#27): Gate B [07/10]: FastAPI health endpoint + app factory (H-1)

- App factory pattern (FUND-8): create_app() produces fresh app per test
- Logging config (structured, no secrets)
- Config validation: SLAB_AES_KEY required, WOO_BASE_URL HTTPS-only
- GET /api/health returns 200 {status: ok, version, woo_reachable: false}
- SQLite + alembic skeleton: full DATA-MODEL schema, initial migration
- API contract tests via httpx TestClient: 5 cases all green
  - test_returns_200, test_returns_ok_status, test_woo_reachable_false
  - test_response_shape, test_with_test_client_lifespan (FUND-9/10)

backend/alembic/versions/2026_9_7_initial_schema.py

@@ -0,0 +1,178 @@
+"""initial schema.
+
+Revision ID: initial
+Revises:
+Create Date: 2026-09-07
+"""
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = "initial"
+down_revision = None
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    # slabs
+    op.create_table(
+        "slabs",
+        sa.Column("id", sa.Text(), nullable=False, primary_key=True),
+        sa.Column("sku", sa.String(length=24), nullable=False),
+        sa.Column("status", sa.Text(), nullable=False, server_default="draft"),
+        sa.Column("length_in", sa.Float(), nullable=False),
+        sa.Column("thickness_in", sa.Float(), nullable=False),
+        sa.Column("sqft", sa.Float(), nullable=True),
+        sa.Column("bdft", sa.Float(), nullable=True),
+        sa.Column("width_min_in", sa.Float(), nullable=True),
+        sa.Column("width_max_in", sa.Float(), nullable=True),
+        sa.Column("width_avg_in", sa.Float(), nullable=True),
+        sa.Column("species_id", sa.Integer(), nullable=True),
+        sa.Column("wood_category_ids", sa.JSON(), nullable=True),
+        sa.Column("edge_type_term_id", sa.Integer(), nullable=True),
+        sa.Column("figure_term_ids", sa.JSON(), nullable=True),
+        sa.Column("grade_term_ids", sa.JSON(), nullable=True),
+        sa.Column("thickness_term_id", sa.Integer(), nullable=True),
+        sa.Column("moisture_term_id", sa.Integer(), nullable=True),
+        sa.Column("fig_tag_ids", sa.JSON(), nullable=True),
+        sa.Column("feat_tag_ids", sa.JSON(), nullable=True),
+        sa.Column("price_per_bdft", sa.Float(), nullable=True),
+        sa.Column("price", sa.Float(), nullable=False),
+        sa.Column("price_source", sa.Text(), nullable=True),
+        sa.Column("title", sa.Text(), nullable=True),
+        sa.Column("short_title", sa.Text(), nullable=True),
+        sa.Column("description", sa.Text(), nullable=True),
+        sa.Column("content_source", sa.Text(), nullable=True),
+        sa.Column("client_rev", sa.Integer(), nullable=False, server_default="1"),
+        sa.Column("server_rev", sa.Integer(), nullable=False, server_default="1"),
+        sa.Column("created_at", sa.Text(), nullable=False, server_default=sa.text("datetime('now')")),
+        sa.Column("updated_at", sa.Text(), nullable=False, server_default=sa.text("datetime('now')")),
+        sa.Column("inference_thread_id", sa.Text(), nullable=True),
+        sa.CheckConstraint("length_in >= 0"),
+        sa.CheckConstraint("thickness_in >= 0"),
+        sa.CheckConstraint("price >= 0"),
+        sa.UniqueConstraint("sku"),
+    )
+    op.create_index("idx_slabs_status", "slabs", ["status"])
+    op.create_index("idx_slabs_updated_at", "slabs", ["updated_at"])
+
+    # slab_photos
+    op.create_table(
+        "slab_photos",
+        sa.Column("id", sa.Text(), nullable=False, primary_key=True),
+        sa.Column("slab_id", sa.Text(), nullable=False),
+        sa.Column("kind", sa.Text(), nullable=False),
+        sa.Column("role", sa.Text(), nullable=True),
+        sa.Column("seq", sa.Integer(), nullable=False, server_default="0"),
+        sa.Column("original_path", sa.Text(), nullable=True),
+        sa.Column("processed_path", sa.Text(), nullable=True),
+        sa.Column("created_at", sa.Text(), server_default=sa.text("datetime('now')")),
+        sa.ForeignKeyConstraint(["slab_id"], ["slabs.id"], ondelete="CASCADE"),
+    )
+
+    # pricing_rules
+    op.create_table(
+        "pricing_rules",
+        sa.Column("id", sa.Text(), nullable=False, primary_key=True),
+        sa.Column("species", sa.Text(), nullable=False),
+        sa.Column("price_per_bdft", sa.Float(), nullable=False),
+        sa.Column("created_at", sa.Text(), server_default=sa.text("datetime('now')")),
+        sa.Column("updated_at", sa.Text(), server_default=sa.text("datetime('now')")),
+        sa.UniqueConstraint("species"),
+    )
+
+    # woo_categories
+    op.create_table(
+        "woo_categories",
+        sa.Column("woo_id", sa.Integer(), nullable=False, primary_key=True),
+        sa.Column("name", sa.Text(), nullable=True),
+        sa.Column("slug", sa.Text(), nullable=True),
+        sa.Column("parent_id", sa.Integer(), nullable=True),
+        sa.Column("synced_at", sa.Text(), nullable=True),
+        sa.UniqueConstraint("woo_id"),
+    )
+
+    # woo_attributes
+    op.create_table(
+        "woo_attributes",
+        sa.Column("woo_id", sa.Integer(), nullable=False, primary_key=True),
+        sa.Column("name", sa.Text(), nullable=True),
+        sa.Column("slug", sa.Text(), nullable=True),
+        sa.Column("type", sa.Text(), server_default="select"),
+        sa.Column("synced_at", sa.Text(), nullable=True),
+        sa.UniqueConstraint("woo_id"),
+    )
+
+    # woo_attribute_terms
+    op.create_table(
+        "woo_attribute_terms",
+        sa.Column("woo_id", sa.Integer(), nullable=False, primary_key=True),
+        sa.Column("attribute_id", sa.Integer(), nullable=False),
+        sa.Column("name", sa.Text(), nullable=True),
+        sa.Column("slug", sa.Text(), nullable=True),
+        sa.Column("synced_at", sa.Text(), nullable=True),
+        sa.ForeignKeyConstraint(["attribute_id"], ["woo_attributes.woo_id"]),
+        sa.UniqueConstraint("woo_id"),
+    )
+
+    # woo_tags
+    op.create_table(
+        "woo_tags",
+        sa.Column("woo_id", sa.Integer(), nullable=False, primary_key=True),
+        sa.Column("name", sa.Text(), nullable=True),
+        sa.Column("slug", sa.Text(), nullable=True),
+        sa.Column("synced_at", sa.Text(), nullable=True),
+        sa.UniqueConstraint("woo_id"),
+    )
+
+    # settings
+    op.create_table(
+        "settings",
+        sa.Column("key", sa.Text(), nullable=False, primary_key=True),
+        sa.Column("value_enc", sa.LargeBinary(), nullable=True),
+        sa.Column("updated_at", sa.Text(), server_default=sa.text("datetime('now')")),
+    )
+
+    # sync_log
+    op.create_table(
+        "sync_log",
+        sa.Column("id", sa.Integer(), nullable=False, autoincrement=True, primary_key=True),
+        sa.Column("slab_id", sa.Text(), nullable=True),
+        sa.Column("sku", sa.Text(), nullable=True),
+        sa.Column("woo_product_id", sa.Integer(), nullable=True),
+        sa.Column("status", sa.Text(), nullable=True),
+        sa.Column("http_status", sa.Integer(), nullable=True),
+        sa.Column("error", sa.Text(), nullable=True),
+        sa.Column("detail", sa.Text(), nullable=True),
+        sa.Column("payload_hash", sa.Text(), nullable=True),
+        sa.Column("created_at", sa.Text(), server_default=sa.text("datetime('now')")),
+    )
+
+    # inference_log
+    op.create_table(
+        "inference_log",
+        sa.Column("id", sa.Integer(), nullable=False, autoincrement=True, primary_key=True),
+        sa.Column("slab_id", sa.Text(), nullable=True),
+        sa.Column("call", sa.Text(), nullable=True),
+        sa.Column("request_payload", sa.Text(), nullable=True),
+        sa.Column("response_payload", sa.Text(), nullable=True),
+        sa.Column("created_at", sa.Text(), server_default=sa.text("datetime('now')")),
+    )
+
+
+def downgrade() -> None:
+    op.drop_table("inference_log")
+    op.drop_table("sync_log")
+    op.drop_table("settings")
+    op.drop_table("woo_tags")
+    op.drop_table("woo_attribute_terms")
+    op.drop_table("woo_attributes")
+    op.drop_table("woo_categories")
+    op.drop_table("pricing_rules")
+    op.drop_table("slab_photos")
+    op.drop_index("idx_slabs_updated_at", table_name="slabs")
+    op.drop_index("idx_slabs_status", table_name="slabs")
+    op.drop_table("slabs")