Dependencies are ~2 years stale; LangGraph needs a migration

[kowshikdev]

Problem

langgraph==0.2.45
langchain-core==0.3.20
litellm==1.42.6
streamlit==1.40.1

LangGraph's API changed substantially after 0.2.x. This is not a version bump — expect real migration work around graph construction, state handling and checkpointing.

Since the orchestration layer is the heart of this project, this blocks essentially everything else.

Proposed solution

1. Get the current stack running first (see the end-to-end issue) so there is a baseline to compare against.
2. Read the LangGraph migration notes for 0.2 → current and inventory the breaking changes against orchestration/.
3. Migrate incrementally, one workflow at a time, rather than a big-bang upgrade.
4. Pin exact versions afterwards and add Dependabot.