fix(fleet): harden operator sends for release

docs/scratchpads/2026-06-20-fleet-release-hardening.md

@@ -0,0 +1,35 @@
+# Fleet release hardening
+
+## Objective
+
+Harden the Mosaic local fleet release path for operator sends, tmux/systemd verification, package contents, and dogfood release documentation.
+
+## Constraints
+
+- Do not edit `docs/TASKS.md`.
+- Do not change production deployment refs.
+- Keep fleet transport generic and named-socket safe.
+- Preserve strict roster validation.
+- Add tests first or alongside fixes.
+
+## Plan
+
+1. Add regression tests for deterministic `mosaic agent send` source labels.
+2. Strengthen fleet status/verify/package/install-systemd coverage.
+3. Implement focused CLI/source-label changes.
+4. Update local canary documentation with dogfood preflight.
+5. Run formatting, targeted tests, typecheck, lint, and package dry-run evidence.
+
+## Evidence Log
+
+- Started from existing `docs/PRD.md`; durable local fleet canary is in v0.1.0 scope.
+- Loaded `mosaic-fleet-operations` skill; key constraints are isolated tmux sockets, no default tmux positive tests, and `active (exited)` is not liveness.
+- TDD red: `pnpm --filter @mosaicstack/mosaic test -- src/commands/fleet.spec.ts` initially failed because `node_modules` was absent; after `pnpm install`, the new source-label tests failed on missing `-S`, missing helper, and unknown `--source-label`.
+- Green implementation: `mosaic agent send` now passes `-S <hostname>:operator` by default and accepts `--source-label` / `--source` overrides.
+- Test coverage added for tmux-based fleet verify liveness, package `files` allowlist containing `framework`, and explicit operator source-label command construction.
+- Formatting: `pnpm exec prettier --write packages/mosaic/src/commands/fleet.ts packages/mosaic/src/commands/fleet.spec.ts docs/guides/fleet-local-canary.md docs/scratchpads/2026-06-20-fleet-release-hardening.md`.
+- Targeted tests: `pnpm --filter @mosaicstack/mosaic test -- src/commands/fleet.spec.ts src/cli-smoke.spec.ts` passed with 49 tests.
+- Typecheck: `pnpm typecheck` passed.
+- Lint: `pnpm lint` passed.
+- Package dry-run: `npm pack --dry-run --json` from `packages/mosaic` included `framework/fleet`, `framework/systemd/user`, `framework/tools/fleet/start-agent-session.sh`, and `framework/tools/tmux/{agent-send.sh,send-message.sh}`.
+- Review: `~/.config/mosaic/tools/codex/codex-code-review.sh --uncommitted` approved the supplied diff with no findings; the review tool noted its read-only sandbox could not inspect files directly.