Clean-reinstall the local Singularity Flow product

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Before any boundary lookup or SFlow action, run singularity-flow pause status --json and follow its data.agentInstruction. If data.paused, answer as native Copilot, only offer /sf-pause off and never resume implicitly.

<!-- sflow-output-contract: deterministic-mutation -->

Output contract: Let the CLI validate and mutate state; preserve its exact result, warnings, publication status, artifacts, and next actions. Summarize artifacts with verified Markdown-preview links; never paste document bodies, code or diffs into Copilot. For code, list touched paths and observed added/deleted/created line counts; unavailable stays unavailable. Use existing evidence, not extra calls solely for display. Summaries, links and opened previews are not human review or approval. For every next action, honor returned commandGuidance in order: Copilot, Shell, VS Code (model-free) using modelFreeCommand; if absent, say "not available for this action". Missing Copilot: "no verified equivalent". Never invent routes.

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Boundary: machine-local; no repository or Story required. Use explicit arguments or SFlow-returned paths; never search $HOME or infer a repository. Use exact CLI-returned paths. repositoryPath is command cwd, not a prefix for absolute file paths. Never rebase paths or strip .git/worktrees. Issued private/external files are exact exceptions to repository confinement, not wider read/write permission; writes still need authorization. Resolve relative paths only against their declared base. On failure, preserve the path and error; never search or recreate it. Preserve the complete preview, verification, recovery command, and receipt path.

It replaces product tooling only and never modifies, deletes, scans, fetches, checks out, commits or pushes a Git repository. It preserves every repository singularity/, .singularity/, and .git/singularity-flow/ directory; all workspace directories and registrations; VS Code state; credentials; Node.js; npm; and personal Copilot skills that lack the managed marker.

1. Require the contributor to identify the Singularity Flow source checkout to install. From a promoted release directory instead, run sf-install --release-dir "<DIR>" --artifact-key "<PUBLIC-KEY>" with --dry-run, then steps 3-7 with --confirm "<EXACT CONFIRMATION>"; without either flag it applies at once.
2. Preview with sf-reinstall --checkout "<CHECKOUT>" --dry-run. --registry "<URL>" selects a company registry; --cli-only omits Copilot/VS Code only by request. --skip-tests needs explicit consent, never inferred from failures. Keep build/artifact checks; disclose skipped tests.
3. Show the complete Replace, Preserve, artifact hashes, fingerprint and any unavailable optional surface; never summarize away a preserved-data guarantee.
4. The contributor must give the exact fingerprint-bound confirmation in a separate response; never generate, infer or submit it for them.
5. After that explicit response, run sf-reinstall --checkout "<CHECKOUT>" --confirm "<EXACT CONFIRMATION>". Repeat the preview's --registry, --cli-only, --skip-tests and telemetry choices.
6. Build/test/package output is staging, not activation; matching versions do not prove build identity. Report full installation only when the final banner is exactly Singularity Flow product activation — COMPLETE AND VERIFIED, the installed singularity-flow --build identity matches the admitted candidate, all selected surfaces verify (including singularity-flow plugin verify --json when Copilot is selected), and ~/.singularity-flow/installations/current.json is committed. Report an explicitly narrowed install as Singularity Flow product activation — PARTIAL BY REQUEST. An unavailable optional manager reports Singularity Flow product activation — COMPLETE WITH SKIPS and the skipped surface. Keep the (TESTS SKIPPED) banner suffix; never claim those tests passed.
7. Report the verified CLI build, VS Code extension, Copilot plugin, direct-skill inventory and the committed installation receipt.

Never substitute reset commands, git clean or home-directory search. Without a recognized final banner, show the exact recovery command; never infer success. A legacy install lacking retained prior bytes recovers forward from the verified candidate; never claim rollback.