✨ Compile doc code fences into tests

Every `ts`-tagged fence in README.md / CONTRIBUTING.md now becomes an
executed `node:test` case in a gitignored generated file, so a
documented example cannot drift from the API. The generator hoists and
merges the leading imports, rewrites the library specifier to the
`#test-tiny-pattern-ts` alias, and rejects a fence with no describing
paragraph or one that re-imports a prelude module.

CI regenerates via `pretest:ci`; `create:doc-tests` runs the generator,
formats, then typechecks the output against a scoped tsconfig that
relaxes `noUnusedLocals`. c8's default excludes already omit the
generated `*.test.ts`, so `test:ci` is unchanged.

package.json

@@ -28,7 +28,8 @@
     "type": "module",
     "sideEffects": false,
     "imports": {
-        "#test-utils/*": "./src/util/__tests__/*"
+        "#test-utils/*": "./src/util/__tests__/*",
+        "#test-tiny-pattern-ts": "./src/index.ts"
     },
     "exports": {
         ".": {
@@ -47,7 +48,8 @@
         "check:oxfmt": "oxfmt --check ${LEFTHOOK_FILES:-.}",
         "check:oxlint": "oxlint ${LEFTHOOK_FILES:-src scripts}",
         "check:tsc": "tsc",
-        "clean": "rm -rf dist coverage",
+        "clean": "rm -rf dist coverage src/doc-test/__generated__/*.test.ts",
+        "create:doc-tests": "node --strip-types scripts/create-doc-tests.ts && sh -c 'oxfmt src/doc-test/__generated__/*.test.ts' && tsc -p src/doc-test/tsconfig.json",
         "fix": "npm run fix:oxlint && npm run fix:oxfmt",
         "fix:oxfmt": "oxfmt ${LEFTHOOK_FILES:-.}",
         "fix:oxlint": "oxlint --fix src scripts",
@@ -58,6 +60,7 @@
         "maintain:knip": "knip --include dependencies,exports,files",
         "maintain:outdated": "check-outdated --ignore-pre-releases --ignore-packages @types/node",
         "test": "npm run check:tsc && node --test --strip-types \"src/**/*.test.ts\"",
+        "pretest:ci": "npm run create:doc-tests",
         "test:ci": "c8 --all --include \"src/**/*.ts\" --reporter=text --reporter=lcov --reporter=html --100 node --test --strip-types \"src/**/*.test.ts\"",
         "test:unit": "node --test --strip-types \"src/**/*.test.ts\"",
         "verify": "npm run check && npm run test:unit",
@@ -83,6 +86,7 @@
         "expect-type": "1.4.0",
         "knip": "^6.34.0",
         "lefthook": "^2.1.12",
+        "mdast-util-from-markdown": "^2.0.3",
         "oxfmt": "^0.70.0",
         "oxlint": "^1.83.0",
         "oxlint-tsgolint": "^7.0.2001",