Ship a zero-node Core installer with opt-in local sandboxes

[SaladDay]

Install Core, the existing Web console and PostgreSQL with zero execution nodes by default. Local sandbox provisioning is explicit:

./install.sh
./install.sh --sandbox-provider true --provider microsandbox
./install.sh --sandbox-provider true --provider docker

Default Core receives no Docker socket, host devices or managed-provider configuration, and installation imports no Runtime or invokes a model. Core-only and Web-only modes remain available. Repeat installation preserves identities, secrets and data; automatic revision/provider migration is excluded.

The matched distribution contains immutable service/Runtime images, source provenance and checksums, a public landing page, and deployment/API/operations docs. A standalone server-side console proxy keeps the Core caller key out of browser assets. Optional microsandbox runs Core as a native user service to preserve compute during a Core restart. Its SDK-owned /environment disk supports workspace export and native full checkpoint recovery. The build entrypoint normalizes payload permissions for non-root services even when invoked with umask 077.

Validation

Candidate a5b4d140f5dd3ee6315baa5a90e6700882c73562, based on main e4b124c:

• Full make check on zju with a dedicated PostgreSQL database passed, including 94/94 browser checks; 33 installer tests and 5 manifest tests passed.
• Exact archive built, freshly extracted and checksum/provenance verified on mx1 Linux amd64/KVM. Default Core/Web/database installation passed 45 initial and 25 stop/restart checks, retaining zero Sessions/nodes and no execution authority.
• Docker Core-only + Web-only installation/repeat/authentication checks passed. Codex, Claude Code and MiniMax Code each passed real Kimi execution, Files/Artifact byte checks, Core restart continuation and cancellation: 9/9.
• Explicit microsandbox passed the same three-harness 9/9 real matrix, unchanged native process identity across Core restart, 73 tenant/secret checks and Artifact deduplication. Final Codex additionally passed default 300-second idle full checkpoint and real resume, preserving history/files/memory with no duplicate execution or cancelled-command replay. The preceding storage-qualified candidate also passed idle recovery for all three harnesses; those earlier results retain their separate revision.
• Independent Astra high full-diff review and follow-up review passed. The reproduced umask issue was corrected in the shipped entrypoint. Private launcher/probe mistakes remain in acceptance evidence and did not require production workarounds.

Archive SHA256: 88172cde7f35f6cc56cdc89992e5b7b31838eb2fa5d5b73f0478af60e04c6032.

Evidence: ~/.parsar/acceptance/landing-mx1-zero/ on mx1 and the operator workstation; build and full-gate evidence under ~/.parsar/acceptance/landing-mx1-build-release/ and landing-mx1-check/ on zju. Test Sessions/Runtime resources are released through the public API; the default zero-node deployment is retained for inspection.

Boundaries

Linux amd64 is qualified. Microsandbox requires host KVM access and user-service lingering; host reboot/cold recovery and automatic upgrades/provider migration are not qualified. No Web application redesign, future node enrollment, PR #30, advanced Templates or new public protocol behavior is included. This is installer acceptance, not a claim of complete Agents API compatibility.