- services/domain/llm-router and services/domain/user-deletion still had
colocated *.test.ts; moved them into the local tests/ subdir so every
service module follows the same layout as billing/, admin/*/, etc.
- routes/oidc/ wasn't an independent route group — it's wholly consumed
by routes/auth/index.ts (electron-callback relay + OIDC bearer token
helper). Moved to routes/auth/oidc/ to reflect that ownership.
- Fixed the relative imports in src/libs/tests/{auth,env,request-auth,
ws-auth}.test.ts. They were moved to libs/tests/ in the previous
commit without updating the './<source>' specifiers; typecheck only
caught it once the rewriter ran across the tree.
pnpm typecheck passes; eslint matches the main baseline.