fix(testing): make vitest 4 constructor mocks type-check cleanly

- logging-session & mcp-oauth mocks: a class passed to mockImplementation has
  a construct signature that isn't assignable to its (...args) => any parameter,
  failing tsc. Use named function declarations instead (constructable via
  Reflect.construct, assignable to mockImplementation, and not rewritten to
  arrows by biome's useArrowFunction).
- database.mock.ts: vitest 4's generic vi.fn typings no longer break the
  self-referential cycle on the transaction callback's tx param; loosen tx and
  annotate the callback's return type to resolve the implicit-any errors.

Author: waleedlatif1

packages/testing/src/mocks/database.mock.ts

@@ -155,7 +155,7 @@ const set = vi.fn(() => ({ where }))
 const update = vi.fn(() => ({ set }))
 const del = vi.fn(() => ({ where }))
 const transaction: ReturnType<typeof vi.fn> = vi.fn(
-  async (cb: (tx: typeof dbChainMock.db) => unknown) => cb(dbChainMock.db)
+  async (cb: (tx: any) => unknown): Promise<unknown> => cb(dbChainMock.db)
 )
 
 export const dbChainMockFns = {

packages/testing/src/mocks/logging-session.mock.ts

@@ -31,28 +31,36 @@ export const loggingSessionMockFns = {
   mockMarkAsFailed: vi.fn().mockResolvedValue(undefined),
 }
 
+/**
+ * Builds the object returned by each `new LoggingSession(...)` call. Declared as
+ * a named function (not an arrow) so it stays constructable under vitest 4's
+ * `Reflect.construct` path while remaining assignable to `mockImplementation`; a
+ * returned object overrides the constructed instance.
+ */
+function buildLoggingSessionInstance() {
+  return {
+    start: loggingSessionMockFns.mockStart,
+    complete: loggingSessionMockFns.mockComplete,
+    completeWithError: loggingSessionMockFns.mockCompleteWithError,
+    completeWithCancellation: loggingSessionMockFns.mockCompleteWithCancellation,
+    completeWithPause: loggingSessionMockFns.mockCompleteWithPause,
+    safeStart: loggingSessionMockFns.mockSafeStart,
+    waitForCompletion: loggingSessionMockFns.mockWaitForCompletion,
+    waitForPostExecution: loggingSessionMockFns.mockWaitForPostExecution,
+    safeComplete: loggingSessionMockFns.mockSafeComplete,
+    safeCompleteWithError: loggingSessionMockFns.mockSafeCompleteWithError,
+    safeCompleteWithCancellation: loggingSessionMockFns.mockSafeCompleteWithCancellation,
+    safeCompleteWithPause: loggingSessionMockFns.mockSafeCompleteWithPause,
+    markAsFailed: loggingSessionMockFns.mockMarkAsFailed,
+  }
+}
+
 /**
  * Constructor-shaped mock for `LoggingSession`. Each `new LoggingSession(...)`
  * call returns an object whose methods point at the shared `vi.fn()` refs in
  * `loggingSessionMockFns`.
  */
-export const LoggingSessionMock = vi.fn().mockImplementation(
-  class {
-    start = loggingSessionMockFns.mockStart
-    complete = loggingSessionMockFns.mockComplete
-    completeWithError = loggingSessionMockFns.mockCompleteWithError
-    completeWithCancellation = loggingSessionMockFns.mockCompleteWithCancellation
-    completeWithPause = loggingSessionMockFns.mockCompleteWithPause
-    safeStart = loggingSessionMockFns.mockSafeStart
-    waitForCompletion = loggingSessionMockFns.mockWaitForCompletion
-    waitForPostExecution = loggingSessionMockFns.mockWaitForPostExecution
-    safeComplete = loggingSessionMockFns.mockSafeComplete
-    safeCompleteWithError = loggingSessionMockFns.mockSafeCompleteWithError
-    safeCompleteWithCancellation = loggingSessionMockFns.mockSafeCompleteWithCancellation
-    safeCompleteWithPause = loggingSessionMockFns.mockSafeCompleteWithPause
-    markAsFailed = loggingSessionMockFns.mockMarkAsFailed
-  }
-)
+export const LoggingSessionMock = vi.fn().mockImplementation(buildLoggingSessionInstance)
 
 /**
  * Static mock module for `@/lib/logs/execution/logging-session`.

packages/testing/src/mocks/mcp-oauth.mock.ts

@@ -43,6 +43,16 @@ export class McpOauthInsecureUrlErrorMock extends Error {
   }
 }
 
+/**
+ * Returns the provider config back as the constructed instance, matching the
+ * original identity passthrough. Declared as a named function (not an arrow) so
+ * it stays constructable under vitest 4's `Reflect.construct` path while
+ * remaining assignable to `mockImplementation`.
+ */
+function buildSimMcpOauthProvider(value: object) {
+  return value
+}
+
 /**
  * Static mock module for `@/lib/mcp/oauth`.
  *
@@ -70,11 +80,5 @@ export const mcpOauthMock = {
   withMcpOauthRefreshLock: mcpOauthMockFns.mockWithMcpOauthRefreshLock,
   McpOauthRedirectRequired: McpOauthRedirectRequiredMock,
   McpOauthInsecureUrlError: McpOauthInsecureUrlErrorMock,
-  SimMcpOauthProvider: vi.fn().mockImplementation(
-    class {
-      constructor(value: object) {
-        Object.assign(this, value)
-      }
-    }
-  ),
+  SimMcpOauthProvider: vi.fn().mockImplementation(buildSimMcpOauthProvider),
 }