greenfield(fomo-lin): codify true-greenfield doctrine + mosaic-greenfield-reset protocol

Co-Authored-By: Claude Fable 5 <[email protected]>

docs/reports/greenfield/fomo-lin.md

@@ -270,3 +270,24 @@ three items — template-only PreToolUse mutator-gate entry, template-only Stop
 receipt-observer entry, operator-only mcpServers.sequential-thinking block (whose omission
 from the template is F7's root cause). Spec: base = template − two gate hooks + mcpServers;
 promotion overlay = the two gate hooks, nothing more. Sent to fred (20260808T200337Z).
+
+## Box doctrine — true greenfield, repeatable full-cycle testing (Jason, 2026-08-08)
+
+fomo-lin's defining property: the test operator (scooby) is NOT a fleet seat — comms
+watcher, git identity, nvm/Node, and repos live entirely outside Mosaic. Therefore Mosaic
+can be wiped to TRUE ZERO and reinstalled in full, repeatedly, to test protocols
+end-to-end per cycle (each W-F fixture drop, each next release).
+
+Codified as `~/.local/bin/mosaic-greenfield-reset` (dry-run by default, `--yes` to
+execute): removes units/gateway/npm packages/npmrc scope/`~/.config/mosaic`/`~/.mosaic`/
+mosaic-written `~/.claude` files (settings reset to stock)/workaround shims; preserves the
+operator layer (watcher, git creds, nvm, repos, `~/.claude` auth + session state, baseline
+backup). Ends with a verify-zero checklist.
+
+Known boundary impurities the reset explicitly handles: `~/.claude/settings.json` is
+mosaic-written today (its QA hooks fire even in the operator's own session — observed:
+prevent-memory-write blocked an operator write), and the F9 probe shim sits in
+`~/.local/bin`. Both are named in the script rather than left as ambient state.
+
+Not executed yet — current install (next lane + prototype) is the substrate Fred's W-F1
+fixtures target. First full cycle runs when the next testable artifact lands.