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/pkg/vector/vdbs/seekdb.py

@@ -7,7 +7,13 @@ from typing import Any, Dict, List
 
 
 from langbot.pkg.core import app
-from langbot.pkg.vector.vdb import VectorDatabase, SearchType
+from langbot.pkg.utils import bounded_executor
+from langbot.pkg.vector.vdb import (
+    VectorDatabase,
+    SearchType,
+    remember_bounded_mapping,
+    runtime_cache_limit,
+)
 
 try:
     import pyseekdb
@@ -90,6 +96,7 @@ class SeekDBVectorDatabase(VectorDatabase):
 
         self._collections: Dict[str, Any] = {}
         self._collection_configs: Dict[str, HNSWConfiguration] = {}
+        self._runtime_cache_limit = runtime_cache_limit(ap)
 
         self._escape_table = str.maketrans(
             {
@@ -103,6 +110,13 @@ class SeekDBVectorDatabase(VectorDatabase):
             }
         )
 
+    async def close(self) -> None:
+        self._collections.clear()
+        self._collection_configs.clear()
+        close = getattr(self.client, 'close', None)
+        if callable(close):
+            await bounded_executor.run_blocking_cleanup(close)
+
     def _normalize_collection_name(self, collection: str) -> str:
         """SeekDB only accepts [a-zA-Z0-9_], while LangBot uses UUID-like KB IDs."""
         normalized = re.sub(r'[^A-Za-z0-9_]', '_', collection)
@@ -132,7 +146,12 @@ class SeekDBVectorDatabase(VectorDatabase):
         if await asyncio.to_thread(self.client.has_collection, collection):
             # Collection exists, get it
             coll = await asyncio.to_thread(self.client.get_collection, collection, embedding_function=None)
-            self._collections[collection] = coll
+            remember_bounded_mapping(
+                self._collections,
+                collection,
+                coll,
+                self._runtime_cache_limit,
+            )
             self.ap.logger.info(f"SeekDB collection '{collection}' retrieved.")
             return coll
 
@@ -145,7 +164,12 @@ class SeekDBVectorDatabase(VectorDatabase):
 
         # Create HNSW configuration
         config = HNSWConfiguration(dimension=vector_size, distance='cosine')
-        self._collection_configs[collection] = config
+        remember_bounded_mapping(
+            self._collection_configs,
+            collection,
+            config,
+            self._runtime_cache_limit,
+        )
 
         # Create collection without embedding function (we manage embeddings externally)
         coll = await asyncio.to_thread(
@@ -155,7 +179,12 @@ class SeekDBVectorDatabase(VectorDatabase):
             embedding_function=None,  # Disable automatic embedding
         )
 
-        self._collections[collection] = coll
+        remember_bounded_mapping(
+            self._collections,
+            collection,
+            coll,
+            self._runtime_cache_limit,
+        )
         self.ap.logger.info(f"SeekDB collection '{collection}' created with dimension={vector_size}, distance='cosine'")
         return coll
 
@@ -243,7 +272,12 @@ class SeekDBVectorDatabase(VectorDatabase):
         # Get collection
         if collection not in self._collections:
             coll = await asyncio.to_thread(self.client.get_collection, collection, embedding_function=None)
-            self._collections[collection] = coll
+            remember_bounded_mapping(
+                self._collections,
+                collection,
+                coll,
+                self._runtime_cache_limit,
+            )
         else:
             coll = self._collections[collection]
 
@@ -349,7 +383,12 @@ class SeekDBVectorDatabase(VectorDatabase):
         # Get collection
         if collection not in self._collections:
             coll = await asyncio.to_thread(self.client.get_collection, collection, embedding_function=None)
-            self._collections[collection] = coll
+            remember_bounded_mapping(
+                self._collections,
+                collection,
+                coll,
+                self._runtime_cache_limit,
+            )
         else:
             coll = self._collections[collection]
 
@@ -374,7 +413,12 @@ class SeekDBVectorDatabase(VectorDatabase):
 
         if collection not in self._collections:
             coll = await asyncio.to_thread(self.client.get_collection, collection, embedding_function=None)
-            self._collections[collection] = coll
+            remember_bounded_mapping(
+                self._collections,
+                collection,
+                coll,
+                self._runtime_cache_limit,
+            )
         else:
             coll = self._collections[collection]
 
@@ -396,7 +440,12 @@ class SeekDBVectorDatabase(VectorDatabase):
 
         if collection not in self._collections:
             coll = await asyncio.to_thread(self.client.get_collection, collection, embedding_function=None)
-            self._collections[collection] = coll
+            remember_bounded_mapping(
+                self._collections,
+                collection,
+                coll,
+                self._runtime_cache_limit,
+            )
         else:
             coll = self._collections[collection]