Add strict TypeScript flags in setup wizard

[matejchalk]

User story

The main advantage of integrating @code-pushup/typescript-plugin is that it allows setting a strict aspirational tsconfig.json, even though the current codebase isn't prepared to meet those standards. This can be set up with 2 tsconfigs - the old config that currently passes compilation, and a derived config with added strict flags for Code PushUp. This facilitates incremental improvements over a longer period of time, with progress being tracked and no blocking build errors.

Real-world example

tsconfig.json

{
  "extends": "@strapi/typescript-utils/tsconfigs/server",
  "compilerOptions": {
    "jsx": "react",
    "outDir": "dist",
    "rootDir": ".",
    "allowJs": true,
    "baseUrl": "./",
    "target": "esnext",
    "skipLibCheck": true,
    "strictNullChecks": true,
    "noUncheckedIndexedAccess": true
  },
  "include": ["./"],
  "exclude": ["node_modules/", "build/", "dist/", ".cache/", ".tmp/"]
}

tsconfig.strict.json

{
  "extends": "./tsconfig.json",
  "compilerOptions": {
    "strict": true,
    "noUncheckedIndexedAccess": true
  }
}

Acceptance criteria

• If the TypeScript plugin is selected in the setup wizard, then there is a further prompt (or CLI argument) to enable additional type-checking flags.
• The user may choose any subset of the Type Checking compiler options.
• The strict, noUncheckedIndexedAccess, and exactOptionalPropertyTypes compiler options are pre-selected.
• The list of available options is filtered. Only options that aren't already enabled are listed.
• If the strict flag is enabled but other flags within this family are disabled (e.g., strictNullChecks or noImplicitAny), then these flags are pre-selected.
• If the user selects some additional compiler flags, then a new tsconfig.strict.json is created.
  • The tsconfig.strict.json extends the existing tsconfig (previously selected by the user in TypeScript plugin setup wizard #1256).
  • The tsconfig.strict.json enables the selected compiler options.
  • The @code-pushup/typescript-plugin setup in code-pushup.config.ts uses the new tsconfig.strict.json instead of the user-provided existing tsconfig.