Split Pi and Hermes Dynamo plugins

[ishandhanani]

This splits the repo into standalone pi-plugin/ and hermes-plugin/ packages. It keeps the Pi provider work isolated while adding the smallest Hermes middleware needed to stamp Dynamo trajectory headers from Hermes session_id.

How This Was Implemented

• Moved the existing Pi provider package, tests, scripts, and skill under pi-plugin/.
• Added hermes-plugin/ with one middleware hook that sets x-dynamo-trajectory-id when Hermes provides session_id.
• Updated CI and repo docs to use the new plugin paths.

Walkthrough

• pi-plugin/: existing Pi provider package and validation assets now live under one folder.
• hermes-plugin/__init__.py: registers an llm_request middleware and preserves explicit Dynamo trajectory headers.
• .github/workflows/integration-smoke.yml: points npm install and smoke script execution at pi-plugin/.
• README.md / CLAUDE.md: document the two-plugin repo layout.

Validation

• cd pi-plugin && npm run check
• cd pi-plugin && npm test
• cd pi-plugin && npm run build
• python3 -m unittest discover -s hermes-plugin/tests
• git diff --check