Port from nanocoai/nanoclaw#2748: Docker's built-in 64 MB /dev/shm silently
breaks shared-memory-hungry workloads inside the sandbox — Chromium/Playwright
renderers crash tabs, and PyTorch DataLoader workers die with 'bus error' /
'insufficient shared memory'. tmpfs is lazily allocated, so the higher ceiling
costs nothing until actually used, and usage still counts against the
container's --memory cgroup limit.
- tools/environments/docker.py: --shm-size 1g in resource args (not
cgroup-gated; tmpfs mount option). Skipped when docker_extra_args already
sets --shm-size, or when configured empty/'0' (Docker default).
- terminal.docker_shm_size config key (DEFAULT_CONFIG + all three
config->TERMINAL_DOCKER_SHM_SIZE env bridges: CLI, gateway, config.py map)
- tests: default emit, custom value, opt-out, extra_args precedence,
helper edge cases (sabotage-verified: default/custom tests fail without
the emit)
