chore(scripts): cover PowerShell's Env: drive, and correct two stale scope summaries (#2146)

Copilot, eleventh review:

- `Set-Item Env:SMOKE_BROWSER firefox` — PowerShell's Env: DRIVE, the other
  standard way to write the environment there — matched none of the patterns.
  Covered now, positional or via -Path/-Value, for Set-Item/New-Item and their
  -ItemProperty forms. A `Get-Item` READ is still not a finding, which has its
  own negative case: reading the variable is not setting it, the same
  distinction as round 5's `echo "SMOKE_BROWSER: firefox"`.

- Two scope summaries had drifted behind the traversal, both saying the guard
  reads only `run` and `env`/`with`: the module header's "ONLY EXECUTABLE
  POSITIONS" paragraph, and the copilot-instructions mirror. Both list the real
  set now — `run`, the `shell` command template at all three levels, and
  `env`/`container.env`/`with`. The mirror one is the AGENTS.md rule this repo
  states about itself, so it is a rule violation rather than a typo.

Signed-off-by: Cliff Hall <cliff@futurescale.com>
Signed-off-by: cliffhall <cliff@futurescale.com>

.github/copilot-instructions.md

@@ -102,7 +102,7 @@ Both exist and do different jobs. Theme files (`src/theme/<Component>.ts`) custo
 
 ## Gates and PR hygiene
 
-- `npm run format` before committing; **`npm run local:gate` before pushing** (`validate` → `coverage` → `verify:build-gate` → `verify:bundle-externals` → `smoke` → `smoke:web:firefox` → `local:storybook`; the Firefox step is local-only and not mirrored in GitHub CI). The gate is named `local:` rather than `ci` on purpose and has **no alias** (#2146) — `npm run ci` is gone, and a workflow that invokes a `local:*` script, a non-Chromium engine pass, `smoke:web:engine`, or sets `SMOKE_BROWSER` to a non-Chromium value fails `test:scripts` via `scripts/lib/workflow-gate.mjs` — as does naming either family through a workflow expression (`smoke:web:${{ matrix.browser }}`). It scans only `run:` scalars and `env:`/`with:` values, so metadata is not a finding. Flag any diff that adds one of those to `.github/workflows/**`, or that reintroduces a `ci`/`ci:*` root script. `npm run validate` is the fast inner-loop check and is **not** a substitute — it runs `test`, not `test:coverage`, so it does zero coverage gating. The canonical CI-vs-local table is in the root README ("Two tiers: GitHub CI and the local gate").
+- `npm run format` before committing; **`npm run local:gate` before pushing** (`validate` → `coverage` → `verify:build-gate` → `verify:bundle-externals` → `smoke` → `smoke:web:firefox` → `local:storybook`; the Firefox step is local-only and not mirrored in GitHub CI). The gate is named `local:` rather than `ci` on purpose and has **no alias** (#2146) — `npm run ci` is gone, and a workflow that invokes a `local:*` script, a non-Chromium engine pass, `smoke:web:engine`, or sets `SMOKE_BROWSER` to a non-Chromium value fails `test:scripts` via `scripts/lib/workflow-gate.mjs` — as does naming either family through a workflow expression (`smoke:web:${{ matrix.browser }}`). It parses the workflow and scans only the executable paths — `run:` scalars, a custom `shell:` command template (step, and `defaults.run.shell` at workflow/job level, since Actions runs it *around* the script), and `env:` / `container.env:` / `with:` values, with YAML aliases resolved — so metadata is not a finding. Flag any diff that adds one of those to `.github/workflows/**`, or that reintroduces a `ci`/`ci:*` root script. `npm run validate` is the fast inner-loop check and is **not** a substitute — it runs `test`, not `test:coverage`, so it does zero coverage gating. The canonical CI-vs-local table is in the root README ("Two tiers: GitHub CI and the local gate").
 - **A dependency bump must land in every install that declares it.** v2 is not a workspace — the root and each `clients/*` have their own `node_modules`, and a client's test project compiles `core/` and `test-servers/src` (which resolve from the **root**) alongside the client's own sources. Bumping a shared dependency in one manifest only puts two versions of it in one `tsc` program; for a recursive-generic surface like zod that exhausts the tsc heap (#1896). `verify:dep-lockstep` fails the build on this — it derives its candidates from what each `tsc` program actually resolves (`tsc --listFilesOnly`, keeping packages that reach one program from two installs), so a package reached only through another package's `.d.ts` counts too (#1965) — so a PR bumping a package the shared sources pull in should update the root **and every client that already lists it** — not every client unconditionally, since a package absent from an install can't skew and adding it there would be a spurious dependency.
 - **A test or smoke must not touch real user state.** The web smokes run against a throwaway catalog via the shared `scripts/lib/prod-web-server.mjs` helper, never the developer's `~/.mcp-inspector/mcp.json` (#1977); the cli/tui smokes drive a temp `--catalog`; `pack:verify`'s `--web` child sets its own `MCP_CATALOG_PATH` for the same reason (#2003 — its App deep link persists a server row). Anything that boots the web backend and then *navigates* it needs that isolation, not just the scripts named `smoke:*`. A new smoke spawning its own server, or teardown that removes a work dir without first awaiting `stopChild` (the #1801 race — `child-cleanup.mjs` exports both halves and both are required), should be flagged.
 - **A smoke must assert the thing survives, not that it started.** `smoke:tui` runs the Ink TUI under a pseudoterminal (`scripts/lib/pty.mjs`) and requires it to still be running `SMOKE_TUI_SURVIVE_MS` after its first frame (`scripts/lib/render-smoke.mjs`) — because it previously settled OK on first paint while the TUI was exiting 1 ~40ms later with `Raw mode is not supported`, and won that race on every machine (#2147). Flag anything that collapses the survival wait back into "resolve on the marker", and any new smoke whose only assertion is that a process printed something once. A smoke walks only its own happy path, so the branch that matters — started, then died — belongs in a `scripts/lib/*.test.mjs` driven against a stub (as with `announced-child.mjs` #2000 and `ensure-test-servers.mjs` #2111), not in the smoke.