[xgtcode]

Summary

• Add unified Docs Autogen workflow for veadk-python preview and archive generation through the new docs runtime.
• Route preview pushes on main and release tags to DOCS_PROJECT=veadk with metadata-aware refs.
• Remove the old docs autogen workflows that used the legacy runtime/token path to avoid duplicate triggers and old auto-merge behavior.

Verification

• git diff --cached --check
• ruby -e 'require "yaml"; YAML.load_file(".github/workflows/docs-autogen.yml"); puts "yaml_ok"'\n- Checked the new workflow has no stale DOCS_AUTOGEN_URL / DOCS_AUTOGEN_TOKEN references.\n\n## Runtime Configuration\nRequired repository configuration before enabling production runs:\n- Repository variable: DOCS_RUNTIME_ENDPOINT\n- Repository secret: DOCS_RUNTIME_API_KEY\n\nDefault output mode is commit_and_mr, so the workflow creates a docs PR and does not auto-merge by default.