docs(site): add interactive architecture map

[jonathanKingston]

Summary

• add a standalone interactive architecture map with nine system views
• add a verified “Main delta” view covering the 46 commits incorporated from current main
• link the map from the public site footer
• keep the artifact dependency-free and responsive, with an accessible relationship-table fallback

Why

The codebase spans Electron main/renderer boundaries, agent orchestration, tool safety, persistent storage, hooks, feature packs, workspace services, and CI infrastructure. This page makes those relationships explorable while tying component descriptions back to checked-in source locations.

User impact

Visitors can open the Architecture page from the site footer, switch between subsystem views, and inspect each component’s responsibilities and source files. The new main-delta view summarizes the architectural impact of recent work in hooks, feature packs, provider policy, terminal context, advisor routing, UI state, roadmap knowledge, CI/security, and runtime dependencies.

Validation

• all 218 unique cited source paths resolve at origin/main commit cf0a14c2
• Prettier and git diff --check pass
• exercised all nine views, inspector updates, and the 13-row responsive relationship fallback in-browser
• npm run check static gates pass: typecheck, ESLint, Prettier, dead-code analysis, oracle checks, and unit-test build
• full parallel test run: 3,413/3,422 passing; the remaining host/timing failures were investigated, representative hook tests pass independently, short-path SSH tests pass with TMPDIR=/tmp, and the macOS /tmp alias assertion predates the incoming main changes

[github-actions]

Merge conflict needs a human

main advanced and screenshot conflicts were resolved automatically, but these non-screenshot files conflict and can't be auto-merged. Resolve them by hand (merge or rebase main):

• site/architecture.html