feat: make sequence the canonical ordered command

[willytop8]

Summary

• make /goal sequence the canonical ordered multi-goal command
• retain the former command and mode spelling as input-only compatibility aliases
• correct the public completion-auditor snapshot type to "normal" | "ordered"
• update user-facing output, README examples, archive/clear documentation, compatibility evidence, tests, and changelog

Why

sequence describes the behavior directly and avoids exposing internal project terminology in the public command surface. Existing scripts remain compatible because the former spelling is still accepted at the parser boundary, while stored state and output stay canonical as ordered.

Testing

• npm run release:check
• 263/263 tests passed
• 98.43% line / 90.29% branch / 90.44% function coverage
• strict NodeNext and Bundler type contracts passed
• 5/5 critical mutants killed
• behavior benchmark: 100/100
• smoke, packed-host, packed-tools, verifier, production audit, and pack dry-run passed

Compatibility

No persisted-state migration is required. Existing sisyphus command and --mode=sisyphus inputs remain supported as compatibility aliases.