drop inherited architecture docs that no longer match the code

AUTOMATION_CONTEXT.md and SIDECAR.md described the multi-tenant scope
model, the seed/ tree, the marketplace, and a single sidecar owning the
queue — all superseded. Fix the stale doc pointers in opencode.json and
CLAUDE.md, and point at TODO.md as the source of truth on direction.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

opencode.json

@@ -4,10 +4,6 @@
     "CLAUDE.md",
     "CONVENTIONS.md",
     "src/apps/CLAUDE.md",
-    "src/apps/dashboard/CLAUDE.md",
-    "src/apps/editor/CLAUDE.md",
-    "src/apps/runtime/CLAUDE.md",
-    "src/servers/CLAUDE.md",
     "src/databases/CLAUDE.md"
   ]
 }