Project config repository templates

Each child directory is a complete project config repository:

default/ is the first picker choice. It is also embedded into the OS worker as the fallback for API callers that omit a template reference.
with-voice/ is a small alternate template used to prove public GitHub template creation end to end.
voice-agent/ runs the realtime voice agent as a guest worker, pulled in from the @iterate-com/voice-agent package rather than committed (see its README).
codemode-tag/ is the <codemode status="..."> response-format experiment: its worker retargets agents to the platform's headless processor and interprets assistant output itself (see its README).

Every template root, and every direct child under its optional apps/ directory, must contain a tsconfig.json; the OS typecheck validates all of them against the current workspace packages.

The OS project-creation form catalogs every direct child of configs/ through Oxlint codegen. Adding a template directory therefore adds it to the same PR's preview dropdown. Every choice uses its actual GitHub reference, pinned to the preview's exact commit before it is copied.

Project creation accepts pnpm-style public GitHub references:

github:owner/repo
github:owner/repo#path:path/to/template
github:owner/repo#branch-or-commit&path:path/to/template
git+https://github.com/owner/repo.git#branch-or-commit&path:path/to/template

The source ref is resolved once, the selected directory is copied into a new config repo root commit, and the resulting project is not linked to the source repository.

Onboarding is a template choice, not an OS feature. A template opts in by handling the root project/created event in worker.ts. It can create any agent shape, append template-local instructions, and use itx.clients to open that agent on connected browser clients. default and with-voice demonstrate the pattern with different ONBOARDING.md prompts; a template without that event case, such as codemode-tag, has no onboarding agent or redirect.