docs: automate syncing of v0.9 schemas to hosted site (#232)

[kaifcodec]

Description

This PR automates the synchronization of v0.9 JSON schemas into the documentation build process. Previously, changes to the specification were not reflected on the hosted site unless manually moved.

Changes

• Workflow Triggers: Added specification/** to the watch list so the docs rebuild whenever a schema is updated.
• Auto-Sync Step: Added a build step to create docs/specification/0.9 and copy the latest .json schemas from the source directory before the MkDocs build.

Fixes #232