feat(auth): authentication module with multi-tenant isolation (RFC-001)

Introduce an always-on auth layer with auto-created admin on first boot,
multi-tenant isolation for threads/stores, and a full setup/login flow.

Backend
- JWT access tokens with `ver` field for stale-token rejection; bump on
  password/email change
- Password hashing, HttpOnly+Secure cookies (Secure derived from request
  scheme at runtime)
- CSRF middleware covering both REST and LangGraph routes
- IP-based login rate limiting (5 attempts / 5-min lockout) with bounded
  dict growth and X-Forwarded-For bypass fix
- Multi-worker-safe admin auto-creation (single DB write, WAL once)
- needs_setup + token_version on User model; SQLite schema migration
- Thread/store isolation by owner; orphan thread migration on first admin
  registration
- thread_id validated as UUID to prevent log injection
- CLI tool to reset admin password
- Decorator-based authz module extracted from auth core

Frontend
- Login and setup pages with SSR guard for needs_setup flow
- Account settings page (change password / email)
- AuthProvider + route guards; skips redirect when no users registered
- i18n (en-US / zh-CN) for auth surfaces
- Typed auth API client; parseAuthError unwraps FastAPI detail envelope

Infra & tooling
- Unified `serve.sh` with gateway mode + auto dep install
- Public PyPI uv.toml pin for CI compatibility
- Regenerated uv.lock with public index

Tests
- HTTP vs HTTPS cookie security tests
- Auth middleware, rate limiter, CSRF, setup flow coverage

backend/packages/harness/deerflow/config/subagents_config.py

@@ -15,6 +15,11 @@ class SubagentOverrideConfig(BaseModel):
         ge=1,
         description="Timeout in seconds for this subagent (None = use global default)",
     )
+    max_turns: int | None = Field(
+        default=None,
+        ge=1,
+        description="Maximum turns for this subagent (None = use global or builtin default)",
+    )
 
 
 class SubagentsAppConfig(BaseModel):
@@ -25,6 +30,11 @@ class SubagentsAppConfig(BaseModel):
         ge=1,
         description="Default timeout in seconds for all subagents (default: 900 = 15 minutes)",
     )
+    max_turns: int | None = Field(
+        default=None,
+        ge=1,
+        description="Optional default max-turn override for all subagents (None = keep builtin defaults)",
+    )
     agents: dict[str, SubagentOverrideConfig] = Field(
         default_factory=dict,
         description="Per-agent configuration overrides keyed by agent name",
@@ -44,6 +54,15 @@ class SubagentsAppConfig(BaseModel):
             return override.timeout_seconds
         return self.timeout_seconds
 
+    def get_max_turns_for(self, agent_name: str, builtin_default: int) -> int:
+        """Get the effective max_turns for a specific agent."""
+        override = self.agents.get(agent_name)
+        if override is not None and override.max_turns is not None:
+            return override.max_turns
+        if self.max_turns is not None:
+            return self.max_turns
+        return builtin_default
+
 
 _subagents_config: SubagentsAppConfig = SubagentsAppConfig()
 
@@ -58,8 +77,26 @@ def load_subagents_config_from_dict(config_dict: dict) -> None:
     global _subagents_config
     _subagents_config = SubagentsAppConfig(**config_dict)
 
-    overrides_summary = {name: f"{override.timeout_seconds}s" for name, override in _subagents_config.agents.items() if override.timeout_seconds is not None}
+    overrides_summary = {}
+    for name, override in _subagents_config.agents.items():
+        parts = []
+        if override.timeout_seconds is not None:
+            parts.append(f"timeout={override.timeout_seconds}s")
+        if override.max_turns is not None:
+            parts.append(f"max_turns={override.max_turns}")
+        if parts:
+            overrides_summary[name] = ", ".join(parts)
+
     if overrides_summary:
-        logger.info(f"Subagents config loaded: default timeout={_subagents_config.timeout_seconds}s, per-agent overrides={overrides_summary}")
+        logger.info(
+            "Subagents config loaded: default timeout=%ss, default max_turns=%s, per-agent overrides=%s",
+            _subagents_config.timeout_seconds,
+            _subagents_config.max_turns,
+            overrides_summary,
+        )
     else:
-        logger.info(f"Subagents config loaded: default timeout={_subagents_config.timeout_seconds}s, no per-agent overrides")
+        logger.info(
+            "Subagents config loaded: default timeout=%ss, default max_turns=%s, no per-agent overrides",
+            _subagents_config.timeout_seconds,
+            _subagents_config.max_turns,
+        )