Promote the `mvp-system` workspace library crate to a standalone application at `apps/myelin`, rebranding the MVP system along with its binaries, node image, and spec.
- workspace `Cargo.toml`: swap member `crates/mvp-system` -> `apps/myelin` and drop `apps` from `exclude` so the app joins the workspace
- `apps/myelin/Cargo.toml`: declare package `myelin` with `autobins = false` and explicit `[[bin]]` targets `myelin-worker`, `myelin-orchestrator`, `myelin-chat`
- `apps/myelin/src`: move the whole `mvp-system` source tree and rebrand module surfaces (`chat/mod.rs`, `prompt/mod.rs`); add `bin/chat.rs` (`myelin::run_chat_from_args`) and delete the old `mvp_chat.rs`
- `apps/myelin/node-image`: relocate the worker image assets from `apps/mvp-node/` (Dockerfile, Dockerfile.base, tinygrad_worker.py, entrypoint, e2e script) and rename `MVP_SYSTEM_SPEC.md` -> `MYELIN_SPEC.md`
- `xtask`: rewrite build/reference paths for the rename (~1000-line churn); add `crates/dashboard/ACTOR_PANEL_SPEC.md`
Signed-off-by: Zachery Aaron Shores-Chmielewski <zacheryasc@gmail.com>
Replace the sprawl of narrow per-implementation test files (and the inline #[cfg(test)] modules embedded in source) with a small set of black-box behavior-guarantee suites keyed to the public modules, per the BEHAVIOR_GUARANTEES spec.
- tests/mod.rs: cut the test module list to local_e2e/node/observability/orchestration/prompt/staging/transport (+local_mock), removing bootstrap_datastream/relay_provisioning/run_plan/stage_controller/shard_*/weight_*/tx_rx_edge_actor/worker_edge_adapter/telemetry/shared_ring_helper_abi/orchestrator_run_fsm files
- add tests/orchestration_guarantees.rs (1074 lines) and staging_guarantees.rs (747) as black-box contract suites over the public RunPlan and StageController surfaces, referencing specs/BEHAVIOR_GUARANTEES.md
- add focused node_guarantees, prompt_guarantees, and transport_guarantees suites covering node-agent runtime-ready reporting, prompt defaults/terminality, and endpoint-advertisement relay masking
- rename local_mock_pipeline_integration to local_e2e_guarantees and observability_surface_guarantees to observability_guarantees
- strip the large inline #[cfg(test)] mod tests blocks from source files (orchestration/app.rs -3215, chat/runtime.rs -790, node/worker_node_runtime.rs -522, vastai/mod.rs, gguf_shard/shard_fetch, etc.) and the #[path]-registered shard_* test mods from lib.rs
- Cargo.toml: drop the harness=false mvp_chat_mock [[test]] target, and remove the python_worker_protocol integration test
Signed-off-by: Zachery Aaron Shores-Chmielewski <zacheryasc@gmail.com>
