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>

tests/unit_tests/provider/conftest.py

@@ -16,6 +16,18 @@ from langbot.pkg.provider.modelmgr import token
 from langbot.pkg.provider.modelmgr.modelmgr import ModelManager
 from langbot.pkg.entity.persistence import model as persistence_model
 from langbot.pkg.discover import engine as discover_engine
+from langbot.pkg.api.http.context import ExecutionContext
+from langbot.pkg.workspace.entities import WorkspaceExecutionBinding
+
+
+TEST_INSTANCE_UUID = 'test-instance'
+TEST_WORKSPACE_UUID = 'test-workspace'
+TEST_GENERATION = 1
+TEST_EXECUTION_CONTEXT = ExecutionContext(
+    instance_uuid=TEST_INSTANCE_UUID,
+    workspace_uuid=TEST_WORKSPACE_UUID,
+    placement_generation=TEST_GENERATION,
+)
 
 
 class FakeProviderAPIRequester(requester.ProviderAPIRequester):
@@ -157,6 +169,26 @@ def mock_app_for_modelmgr():
     app.llm_model_service = AsyncMock()
     app.embedding_models_service = AsyncMock()
     app.monitoring_service = AsyncMock()
+    app.workspace_service = SimpleNamespace(
+        get_execution_binding=AsyncMock(
+            return_value=WorkspaceExecutionBinding(
+                instance_uuid=TEST_INSTANCE_UUID,
+                workspace_uuid=TEST_WORKSPACE_UUID,
+                placement_generation=TEST_GENERATION,
+                write_fenced=False,
+                state='active',
+            )
+        ),
+        get_local_execution_binding=AsyncMock(
+            return_value=WorkspaceExecutionBinding(
+                instance_uuid=TEST_INSTANCE_UUID,
+                workspace_uuid=TEST_WORKSPACE_UUID,
+                placement_generation=TEST_GENERATION,
+                write_fenced=False,
+                state='active',
+            )
+        ),
+    )
 
     return app
 
@@ -184,6 +216,7 @@ def fake_persistence_data():
 
     providers = [
         persistence_model.ModelProvider(
+            workspace_uuid=TEST_WORKSPACE_UUID,
             uuid=provider_uuid,
             name='Test Provider',
             requester='fake-requester',
@@ -191,6 +224,7 @@ def fake_persistence_data():
             api_keys=['test-api-key-1', 'test-api-key-2'],
         ),
         persistence_model.ModelProvider(
+            workspace_uuid=TEST_WORKSPACE_UUID,
             uuid=provider_uuid2,
             name='Test Provider 2',
             requester='another-fake-requester',
@@ -201,6 +235,7 @@ def fake_persistence_data():
 
     llm_models = [
         persistence_model.LLMModel(
+            workspace_uuid=TEST_WORKSPACE_UUID,
             uuid='test-llm-uuid-1',
             name='TestLLM-1',
             provider_uuid=provider_uuid,
@@ -208,6 +243,7 @@ def fake_persistence_data():
             extra_args={'temperature': 0.7},
         ),
         persistence_model.LLMModel(
+            workspace_uuid=TEST_WORKSPACE_UUID,
             uuid='test-llm-uuid-2',
             name='TestLLM-2',
             provider_uuid=provider_uuid,
@@ -218,6 +254,7 @@ def fake_persistence_data():
 
     embedding_models = [
         persistence_model.EmbeddingModel(
+            workspace_uuid=TEST_WORKSPACE_UUID,
             uuid='test-embedding-uuid-1',
             name='TestEmbedding-1',
             provider_uuid=provider_uuid,
@@ -227,6 +264,7 @@ def fake_persistence_data():
 
     rerank_models = [
         persistence_model.RerankModel(
+            workspace_uuid=TEST_WORKSPACE_UUID,
             uuid='test-rerank-uuid-1',
             name='TestRerank-1',
             provider_uuid=provider_uuid2,
@@ -252,6 +290,7 @@ def runtime_provider(fake_persistence_data, mock_app_for_modelmgr):
     requester_inst = FakeProviderAPIRequester(mock_app_for_modelmgr, {'base_url': provider_entity.base_url})
 
     return requester.RuntimeProvider(
+        execution_context=TEST_EXECUTION_CONTEXT,
         provider_entity=provider_entity,
         token_mgr=token_mgr,
         requester=requester_inst,
@@ -263,6 +302,7 @@ def runtime_llm_model(fake_persistence_data, runtime_provider):
     """Provides a RuntimeLLMModel instance for testing."""
     model_entity = fake_persistence_data['llm_models'][0]
     return requester.RuntimeLLMModel(
+        execution_context=TEST_EXECUTION_CONTEXT,
         model_entity=model_entity,
         provider=runtime_provider,
     )
@@ -273,6 +313,7 @@ def runtime_embedding_model(fake_persistence_data, runtime_provider):
     """Provides a RuntimeEmbeddingModel instance for testing."""
     model_entity = fake_persistence_data['embedding_models'][0]
     return requester.RuntimeEmbeddingModel(
+        execution_context=TEST_EXECUTION_CONTEXT,
         model_entity=model_entity,
         provider=runtime_provider,
     )
@@ -286,6 +327,7 @@ def runtime_rerank_model(fake_persistence_data, mock_app_for_modelmgr):
     requester_inst = AnotherFakeRequester(mock_app_for_modelmgr, {'base_url': provider_entity.base_url})
 
     provider = requester.RuntimeProvider(
+        execution_context=TEST_EXECUTION_CONTEXT,
         provider_entity=provider_entity,
         token_mgr=token_mgr,
         requester=requester_inst,
@@ -293,6 +335,7 @@ def runtime_rerank_model(fake_persistence_data, mock_app_for_modelmgr):
 
     model_entity = fake_persistence_data['rerank_models'][0]
     return requester.RuntimeRerankModel(
+        execution_context=TEST_EXECUTION_CONTEXT,
         model_entity=model_entity,
         provider=provider,
     )