test(functions-e2e): point test-app at in-repo durable-functions v4 SDK

The ported BasicNode test-app depended on published durable-functions@^3 and
@azure/functions@^4.11.2. Repoint it at the in-repo v4 compat build so the E2E
suite exercises this branch:

- durable-functions -> file:../../../packages/azure-functions-durable
- @azure/functions -> ^4.16.1 (matches the compat's target extension build)
- overrides += @microsoft/durabletask-js -> file:../../../packages/durabletask-js

The core override is required: the compat pins core to a published version that
predates the Functions worker helpers (processOrchestratorRequest/
processEntityBatchRequest), so without it npm resolves stale published core and
the worker path fails at runtime. Regenerated the test-app lock against the
file: refs (npm ls confirms both resolve to the local packages). The v3-authored
samples build unchanged against the v4 SDK (tsc green).

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
Copilot-Session: 6e5be22b-b727-4ccf-8668-60397bb403a0

Author: YunchuWang