refactor: extract VS Code extension to packages/agent-os-vscode/ (#491) (#568)

* refactor: extract VS Code extension to packages/agent-os-vscode/ (#491)

Moves the VS Code extension from packages/agent-os/extensions/vscode/ to
packages/agent-os-vscode/ as a standalone sibling package.

Why:
- TS security issues were getting filed against the Python agent-os package
- Python security tools (bandit, ruff) cannot scan TypeScript
- No independent versioning — VS Code extension releases were coupled to agent-os
- npm dependencies polluted the agent-os directory

Changes:
- Pure git mv — 32 files renamed, 0 content changes
- Updated tutorial cross-references in README.md and docs/index.md

Closes #491

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* fix(ci): rename dify-plugin to dify in test matrix

The directory was renamed but the CI matrix was not updated,
causing test-integrations (dify-plugin) to fail on every PR.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: imran-siddique

.github/workflows/ci.yml

@@ -97,8 +97,6 @@ jobs:
             import-module: a2a_agentmesh
           - package: crewai-agentmesh
             import-module: crewai_agentmesh
-          - package: dify-plugin
-            import-module: provider
           - package: flowise-agentmesh
             import-module: flowise_agentmesh
           - package: haystack-agentmesh