chore: update configuration and infrastructure

- Add SOCIAL_RUNTIME__TRUSTED_PROXY_IPS to .env.example
- Add SOCIAL_AUTOMATION_SCHEDULER__* config options
- Change SOCIAL_TEST__EMAIL to SOCIAL_TEST__PHONE
- Update app.sh startup script
- Add new database migrations for phone auth and automation

backend/alembic/versions/20260319_0003_add_messages_visibility_mask.py

@@ -0,0 +1,43 @@
+"""add_messages_visibility_mask
+
+Revision ID: 20260319_0003
+Revises: 202603190002
+Create Date: 2026-03-19 18:10:00
+
+"""
+
+from typing import Sequence
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = "20260319_0003"
+down_revision: str | Sequence[str] | None = "202603190002"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+
+def upgrade() -> None:
+    op.add_column(
+        "messages",
+        sa.Column(
+            "visibility_mask",
+            sa.BigInteger(),
+            nullable=False,
+            server_default=sa.text("0"),
+        ),
+    )
+    op.create_index(
+        "ix_messages_session_seq_visibility",
+        "messages",
+        ["session_id", "seq", "visibility_mask"],
+        unique=False,
+    )
+    op.execute("UPDATE messages SET visibility_mask = 1 WHERE visibility_mask = 0")
+
+
+def downgrade() -> None:
+    op.drop_index("ix_messages_session_seq_visibility", table_name="messages")
+    op.drop_column("messages", "visibility_mask")