v0.13.0 — claude-session SDK runtime

SDK-native agent runtime (no tmux required)

New runtime: claude-session

A fully programmatic agent runtime backed by claude-agent-sdk. Drives
ClaudeSDKClient directly — no tmux/screen, no auto-accept TUI handling,
no pane-state classifier. Pro/Max OAuth flat-rate by default (reads
~/.claude/.credentials.json or bridges from a stored OAuth env var
without falling back to pay-per-token API keys).

spec:
  runtime: claude-session
  startup_commands:
    - command: "Your mission text here"

New: sac start --foreground

Streams assistant output to your terminal as it arrives; exits when the
turn completes. Single-target only.

New: sdk_session block on sac show-status --json

{
  "sdk_session": {
    "session_id": "uuid",
    "quota": {"input_tokens": 6, "output_tokens": 14, "turns": 1, ...},
    "heartbeat": {"ts": ..., "pid": ..., "state": "idle"},
    "state_dir": "..."
  }
}

New: project-local agent + state discovery

Walks up from cwd to find a git repo containing .scitex/agent-container/.
In-repo test fixtures override stale globals. Same convention as the
slurm runtime + scitex-hpc reservations.

New: container.runtime: podman

Drop-in for docker (CLI-compatible).

New: in-repo smoke fixture + GitHub workflow

• .scitex/agent-container/agents/sdk-test/sdk-test.yaml
• .github/workflows/sdk-runtime-smoke.yml runs the SDK runtime end-to-end on every push + daily cron

New: skill leaves

• 15_claude-session.md — runtime reference
• 16_claude-session-migration.md — per-agent migration cookbook (parity-check → soak → cutover → rollback)

Breaking

• cursor and aider removed from valid spec.runtime (no working adapter ever shipped).

Docs

• Phase 0–3.5 of the SDK migration (design in GITIGNORED/SDK_MIGRATION_DESIGN.md).