feat(persistence): PostgreSQL assistant store, chat persist fixes, gateway scripts

- Add SQLAlchemy Core repos, pg adapter/compat, assistant_store factory, Alembic bootstrap and migration/cutover scripts.

- Harden chat_message writes (NUL scrub for PG), turn_uuid on attempt failure, WS turn_runner fallbacks and gateway executed_turn_uuid init.

- start_gateway: log paths, PS7 stderr handling via cmd, background stdout/stderr redirect; runtime assistant_runtime_log_dir export.

- Ops: clear_all_chat_sessions with PG-only --postgresql and env-gated wipe; clear_postgres_chat_sessions.ps1.

- Tests: SA repos, pg compat, persist fallback, smoke env isolation; CI and docs touch-ups.

Co-authored-by: Cursor <cursoragent@cursor.com>

svc/persistence/db/tables.py

@@ -0,0 +1,171 @@
+"""SQLAlchemy Core table objects for incremental persistence migration."""
+
+from __future__ import annotations
+
+from sqlalchemy import BigInteger, Column, ForeignKey, Integer, MetaData, Table, Text
+
+metadata = MetaData()
+
+tenant = Table(
+    "tenant",
+    metadata,
+    Column("id", Text, primary_key=True),
+    Column("name", Text, nullable=False),
+    Column("created_at", Text, nullable=False),
+)
+
+bind_code = Table(
+    "bind_code",
+    metadata,
+    Column("code", Text, primary_key=True),
+    Column("tenant_id", Text, nullable=False),
+    Column("role", Text, nullable=False),
+    Column("created_at", Text, nullable=False),
+    Column("used_at", Text, nullable=True),
+    Column("used_by_external_user_id", Text, nullable=True),
+)
+
+app_user = Table(
+    "app_user",
+    metadata,
+    Column("id", Text, primary_key=True),
+    Column("tenant_id", Text, nullable=False),
+    Column("username", Text, nullable=True),
+    Column("display_name", Text, nullable=False),
+    Column("role", Text, nullable=False),
+    Column("password_hash", Text, nullable=True),
+    Column("is_active", Integer, nullable=False, server_default="1"),
+    Column("created_at", Text, nullable=False),
+    Column("avatar_attachment_id", Text, nullable=True),
+)
+
+app_setting = Table(
+    "app_setting",
+    metadata,
+    Column("key", Text, primary_key=True),
+    Column("value", Text, nullable=False),
+    Column("is_secret", Integer, nullable=False, server_default="0"),
+    Column("updated_at", Text, nullable=False),
+)
+
+auth_session = Table(
+    "auth_session",
+    metadata,
+    Column("session_token_hash", Text, primary_key=True),
+    Column("tenant_id", Text, nullable=False),
+    Column("user_id", Text, nullable=False),
+    Column("role", Text, nullable=False),
+    Column("created_at", Text, nullable=False),
+    Column("expires_at", Text, nullable=False),
+    Column("last_seen_at", Text, nullable=False),
+    Column("revoked_at", Text, nullable=True),
+)
+
+chat_session = Table(
+    "chat_session",
+    metadata,
+    Column("id", Text, primary_key=True),
+    Column("title", Text, nullable=False),
+    Column("created_at", Text, nullable=False),
+    Column("last_message_at", Text, nullable=True),
+)
+
+channel_identity_v2 = Table(
+    "channel_identity_v2",
+    metadata,
+    Column("tenant_id", Text, primary_key=True),
+    Column("channel", Text, primary_key=True),
+    Column("account_id", Text, primary_key=True),
+    Column("external_user_id", Text, primary_key=True),
+    Column("user_id", Text, nullable=False),
+    Column("created_at", Text, nullable=False),
+)
+
+channel_identity = Table(
+    "channel_identity",
+    metadata,
+    Column("tenant_id", Text, primary_key=True),
+    Column("channel", Text, primary_key=True),
+    Column("external_user_id", Text, primary_key=True),
+    Column("user_id", Text, nullable=False),
+    Column("created_at", Text, nullable=False),
+)
+
+channel_session_v2 = Table(
+    "channel_session_v2",
+    metadata,
+    Column("tenant_id", Text, primary_key=True),
+    Column("channel", Text, primary_key=True),
+    Column("account_id", Text, primary_key=True),
+    Column("external_chat_id", Text, primary_key=True),
+    Column("external_user_id", Text, primary_key=True),
+    Column("session_id", Text, nullable=False),
+    Column("created_at", Text, nullable=False),
+)
+
+ui_session_owner = Table(
+    "ui_session_owner",
+    metadata,
+    Column("session_id", Text, primary_key=True),
+    Column("tenant_id", Text, nullable=False),
+    Column("user_id", Text, nullable=False),
+    Column("created_at", Text, nullable=False),
+)
+
+chat_message = Table(
+    "chat_message",
+    metadata,
+    Column("id", BigInteger, primary_key=True, autoincrement=True),
+    Column("session_id", Text, ForeignKey("chat_session.id", ondelete="CASCADE"), nullable=False),
+    Column("role", Text, nullable=False),
+    Column("content", Text, nullable=False),
+    Column("tool_calls", Text, nullable=True),
+    Column("attachments", Text, nullable=True),
+    Column("turn_uuid", Text, nullable=True),
+    Column("event_type", Text, nullable=True),
+    Column("event_payload", Text, nullable=True),
+    Column("timestamp", Text, nullable=False),
+)
+
+tool_log = Table(
+    "tool_log",
+    metadata,
+    Column("id", BigInteger, primary_key=True, autoincrement=True),
+    Column("session_id", Text, ForeignKey("chat_session.id", ondelete="CASCADE"), nullable=False),
+    Column("tool_name", Text, nullable=False),
+    Column("specialist", Text, nullable=False, server_default=""),
+    Column("args", Text, nullable=False),
+    Column("result", Text, nullable=False),
+    Column("timestamp", Text, nullable=False),
+    Column("duration_ms", Integer, nullable=True),
+)
+
+trace_event = Table(
+    "trace_event",
+    metadata,
+    Column("id", BigInteger, primary_key=True, autoincrement=True),
+    Column("session_id", Text, nullable=False),
+    Column("trace_id", Text, nullable=False),
+    Column("span_id", Text, nullable=False),
+    Column("parent_span_id", Text, nullable=True),
+    Column("event_type", Text, nullable=False),
+    Column("payload", Text, nullable=False, server_default="{}"),
+    Column("timestamp", Text, nullable=False),
+)
+
+__all__ = [
+    "app_user",
+    "app_setting",
+    "auth_session",
+    "bind_code",
+    "channel_identity",
+    "channel_identity_v2",
+    "channel_session_v2",
+    "chat_message",
+    "chat_session",
+    "metadata",
+    "tenant",
+    "tool_log",
+    "trace_event",
+    "ui_session_owner",
+]