feat(tenancy): add Workspace multi-tenant foundation (#2353)

* Document multi-tenant workspace architecture

* Add OSS and commercial workspace boundaries

* docs: redesign multi-tenant workspace architecture

* feat(tenancy): implement workspace isolation

* docs(tenancy): record verification evidence

* docs(tenancy): revise single-instance SaaS topology

* docs(tenancy): refine architecture options

* docs: finalize cloud v2 multi-tenant decisions

* feat(tenancy): establish cloud isolation foundations

* feat(tenancy): harden shared cloud runtime boundaries

* docs(tenancy): record final isolation verification

* fix(tenancy): close isolation and permission gaps

* docs(tenancy): record final isolation verification

* feat(tenancy): connect cloud workspace control plane

* fix(build): install git for pinned SDK

* docs(cloud): update control plane verification

* chore: update multi-tenant SDK pin

* fix(cloud): skip legacy model sync during startup

* test(cloud): preserve minimal model manager fixtures

* fix(cloud): preserve authenticated account context

* fix(cloud): reuse authenticated account for user info

* feat(cloud): complete Workspace settings navigation

* test(web): cover Workspace dropdown menu

* feat(web): place workspace controls in sidebar

* refactor(web): streamline workspace controls

* style(web): format workspace layout test

* fix(cloud): surface runtime and workspace plan status

* fix(plugin): keep runtime identity stable across restarts

* fix(ui): widen and center workspace switcher

* fix(ui): hide roles from workspace switcher

* fix(ui): align workspace switcher with sidebar entries

* feat(workspace): add in-product collaboration and direct Cloud launch

* style: format collaboration changes

* fix(workspace): bind collaboration APIs to tenant UoW

* fix(cloud): preserve Core-owned collaboration state

* test(cloud): require Space identity for invite registration

* feat(cloud): complete secure invitation experience

* style(web): format invitation flows

* fix(cloud): recover box runtime without unscoped skill reload

* feat(oss): enforce invitation account and owner billing flows

* style: format OSS account service

* test(oss): cover invitation logout handoff

* fix(oss): resolve workspace owner in scoped session

* feat(cloud): harden multi-tenant runtime resources

* fix(cloud): bound runtime restart storms

* fix(cloud): eliminate periodic runtime CPU spikes

* fix(cloud): enforce instance capacity ceilings

* fix(cloud): scope public login capability discovery

* fix(cloud): bound tenant maintenance and monitoring work

* fix(runtime): bound tenant resource amplification

* fix(deps): pin green multi-tenant plugin SDK

* fix(cloud): handle unavailable skill capability

* fix(security): require authentication for image file endpoint (H-2)

- Changed /api/v1/files/image from AuthType.NONE to USER_TOKEN_OR_API_KEY
- Added Permission.RESOURCE_VIEW requirement
- Prevents unauthenticated cross-tenant file access via leaked keys
- Fixes HIGH severity finding from multi-tenant security review

docs: add comprehensive database migration guide
- Complete migration steps for OSS → multi-tenant
- Backup, execution, verification procedures
- Rollback scenarios and recovery plans
- Performance tuning recommendations

* test: add comprehensive cross-tenant isolation tests

Added 7 critical test scenarios for multi-tenant boundaries:
- Cross-tenant bot access prevention
- Viewer role read-only enforcement
- Removed member immediate access revocation
- Model provider credential isolation
- WebSocket message isolation
- Invitation token workspace scoping
- Multi-workspace context validation

These tests address P0-2 coverage gaps for:
- workspaces.py (membership & invitation flows)
- user.py (authentication & authorization)
- websocket_chat.py (real-time isolation)
- plugins.py (resource access control)

docs: finalize database migration guide

* fix(security): resolve M-1, M-2, M-3 security findings

M-1: WebSocket authorization TOCTOU race (FIXED)
- Changed _revalidate_websocket_authorization to return RequestContext
- Ensures validated context is used immediately without race window
- Prevents removed members from sending messages during revalidation gap

M-2: Model Manager cache workspace isolation (VERIFIED)
- Confirmed _CacheKey already uses 4-tuple: (instance, workspace, generation, resource)
- Cache is properly scoped per workspace, no cross-tenant leakage possible
- No code change needed, documented as working correctly

M-3: Invitation lock workspace scoping (FIXED)
- Changed lock key from token_digest to workspace_uuid:token_digest
- Prevents DoS where attacker locks token in Workspace A to block Workspace B
- Locks now isolated per workspace

All MEDIUM severity findings from security review now resolved.

* fix(cloud): unblock tenant CI and enforce knowledge quotas

* fix(tenancy): scope rerank model sync

---------

Co-authored-by: dadachann <185672915+dadachann@users.noreply.github.com>

src/langbot/libs/coze_server_api/client.py

@@ -6,6 +6,22 @@ from typing import Dict, List, Any, AsyncGenerator
 import os
 from pathlib import Path
 
+from langbot.pkg.utils import httpclient
+
+_MAX_COZE_RESPONSE_BYTES = 16 * 1024 * 1024
+_MAX_COZE_EVENT_BYTES = 1024 * 1024
+_MAX_COZE_MEDIA_BYTES = 10 * 1024 * 1024
+
+
+def _read_local_media_limited(path: Path) -> bytes:
+    if path.stat().st_size > _MAX_COZE_MEDIA_BYTES:
+        raise ValueError('Coze upload exceeds the size limit')
+    with path.open('rb') as handle:
+        body = handle.read(_MAX_COZE_MEDIA_BYTES + 1)
+    if len(body) > _MAX_COZE_MEDIA_BYTES:
+        raise ValueError('Coze upload exceeds the size limit')
+    return body
+
 
 class AsyncCozeAPIClient:
     def __init__(self, api_key: str, api_base: str = 'https://api.coze.cn'):
@@ -58,19 +74,24 @@ class AsyncCozeAPIClient:
         if isinstance(file, Path):
             if not file.exists():
                 raise ValueError(f'File not found: {file}')
-            with open(file, 'rb') as f:
-                file = f.read()
+            file = await asyncio.to_thread(_read_local_media_limited, file)
 
         # 处理文件路径字符串
         elif isinstance(file, str):
             if not os.path.isfile(file):
                 raise ValueError(f'File not found: {file}')
-            with open(file, 'rb') as f:
-                file = f.read()
+            file = await asyncio.to_thread(
+                _read_local_media_limited,
+                Path(file),
+            )
 
         # 处理文件对象
         elif hasattr(file, 'read'):
-            file = file.read()
+            file = await asyncio.to_thread(file.read, _MAX_COZE_MEDIA_BYTES + 1)
+        if not isinstance(file, (bytes, bytearray)):
+            raise ValueError('Unsupported Coze upload type')
+        if len(file) > _MAX_COZE_MEDIA_BYTES:
+            raise ValueError('Coze upload exceeds the size limit')
 
         session = await self.coze_session()
         url = f'{self.api_base}/v1/files/upload'
@@ -87,13 +108,18 @@ class AsyncCozeAPIClient:
                 if response.status == 401:
                     raise Exception('Coze API 认证失败，请检查 API Key 是否正确')
 
-                response_text = await response.text()
+                response_text = (
+                    await httpclient.read_limited(
+                        response,
+                        max_bytes=_MAX_COZE_EVENT_BYTES,
+                    )
+                ).decode('utf-8', errors='replace')
 
                 if response.status != 200:
                     raise Exception(f'文件上传失败，状态码: {response.status}, 响应: {response_text}')
                 try:
-                    result = await response.json()
-                except json.JSONDecodeError:
+                    result = json.loads(response_text)
+                except (json.JSONDecodeError, TypeError):
                     raise Exception(f'文件上传响应解析失败: {response_text}')
 
                 if result.get('code') != 0:
@@ -158,7 +184,15 @@ class AsyncCozeAPIClient:
                 if response.status != 200:
                     raise Exception(f'Coze API 流式请求失败，状态码: {response.status}')
 
+                total_bytes = 0
+                chunk_type = 'message'
+                chunk_data = ''
                 async for chunk in response.content:
+                    total_bytes += len(chunk)
+                    if total_bytes > _MAX_COZE_RESPONSE_BYTES:
+                        raise Exception('Coze API stream exceeds the runtime limit')
+                    if len(chunk) > _MAX_COZE_EVENT_BYTES:
+                        raise Exception('Coze API event exceeds the runtime limit')
                     chunk = chunk.decode('utf-8')
                     if chunk != '\n':
                         if chunk.startswith('event:'):