## Summary
- Track last deployed local changes and only redeploy new deltas in auto mode.
- Add per-component fingerprints (server/sandbox/helm) persisted to .cache/cluster-deploy-fast.state.
- Update docs for the new incremental deploy behavior.
```
mise run cluster
....
________________________________________________________
Executed in 75.21 secs fish external
usr time 578.03 millis 0.25 millis 577.78 millis
sys time 364.45 millis 1.22 millis 363.22 millis
```
with a change to `navigator-sandbox` (triggers rust recompile)
```
⟩ time mise run cluster:deploy
[cluster:deploy] $ build/scripts/cluster-deploy-fast.sh
Change detection took 0s
Fast deploy plan:
build server: 0
build sandbox: 1
helm upgrade: 1
...
________________________________________________________
Executed in 25.88 secs fish external
usr time 618.91 millis 0.24 millis 618.67 millis
sys time 557.71 millis 1.54 millis 556.18 millis
```
(most time is spent in docker build)
## Test Plan
- mise run pre-commit
Closes#44
## Summary
- Add `nav sandbox image push --dockerfile <path>` command to build and push custom container images into the cluster
- Fix sandbox Docker build failure caused by OpenClaw installer TTY access
- Fix sandbox proxy crash when network namespace is unavailable (fall back to loopback)
- Add e2e test for the full custom image build and sandbox creation flow
- Rename and rewrite BYOC architecture doc to reflect current state
## Changes
### `navigator-bootstrap`
- New `build` module (`src/build.rs`) with `build_and_push_image()` public API
- Builds via bollard `Docker::build_image()`, streams output to caller
- `.dockerignore` support with glob matching, 8 unit tests
### `navigator-cli`
- Added `SandboxImageCommands::Push` subcommand with `--dockerfile`, `--tag`, `--context`, `--build-arg` flags
- Added `test:e2e:custom-image` mise task
### `navigator-sandbox`
- Proxy now falls back to `127.0.0.1:3128` when no network namespace or explicit bind address is available, instead of erroring out
### Docker / Infra
- Sandbox Dockerfile: replaced OpenClaw native installer (`curl | bash`) with `npm install -g openclaw` to avoid `/dev/tty` failures in Docker build
### Documentation
- Renamed `architecture/sandbox-byoc.md` to `sandbox-custom-containers.md`
- Rewrote doc to describe current behavior (CLI usage, push pipeline, supervisor behavior, design decisions) instead of listing implementation changes
### Tests
- Added `e2e/bash/test_sandbox_custom_image.sh` covering image push + sandbox create with custom image