docs(plan): correct typecheck gate to 'tsc -b --noEmit' (tsconfig.json is a vacuous solution file)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

docs/superpowers/plans/2026-06-06-mui-migration-phase-0-foundation.md

@@ -62,7 +62,7 @@ Expected: devDependencies now show `@types/react@^18.3.x`.
 Run:
 
 ```bash
-npx tsc --noEmit -p tsconfig.json
+npx tsc -b --noEmit
 npm run build:client
 ```
 
@@ -393,7 +393,7 @@ to:
 Run:
 
 ```bash
-npx tsc --noEmit -p tsconfig.json
+npx tsc -b --noEmit
 npm run build:client
 ```
 
@@ -469,7 +469,7 @@ export { default as TextField } from "./TextField";
 Run:
 
 ```bash
-npx tsc --noEmit -p tsconfig.json
+npx tsc -b --noEmit
 ```
 
 Expected: PASS.
@@ -563,7 +563,7 @@ Then, inside `<Routes>`, add a sibling route to `login` (so the showcase renders
 Run:
 
 ```bash
-npx tsc --noEmit -p tsconfig.json
+npx tsc -b --noEmit
 npm run build:client
 ```
 
@@ -642,7 +642,7 @@ git commit -m "style(tokens): refresh light canvas to #f4f3f1 (two-layer refresh
 Run:
 
 ```bash
-npx tsc --noEmit -p tsconfig.json
+npx tsc -b --noEmit
 npx vitest run src/admin/theme.test.ts
 npm run build
 ```