typescript: root a package's published API from package.json, and bind an arrow under as (#847)

[swapnilpaliwal-sd]

Closes #847

What was still broken

Roots for tests, HTTP handlers, decorators and exported_from_entry_module exist on 0.1.4. What remained of cause 1 was that TypeScript never read package.json. A library whose index.ts is imported by its own tests is not an "unimported module", so nothing rooted its public API. That API is the code a consumer outside the repository calls, so it read as unreachable, and unreachable reads as safe to delete.

A second gap showed up on a real state-management library. Its main API is written export const createStore = ((createState) => …) as CreateStore. The as blocked the variable→arrow link, so the arrow was neither a call target of createStore(...) nor the thing createStore exports.

Change

• parser: a new relation, ts_package_entry, the same shape as js_package_entry.
  • It reuses the JS packageEntriesOf walk and adds types and source.
  • Each build-output target (dist/cjs/index.js, esm/index.mjs, dist/index.d.ts) is mapped back to the walked source module. Outcomes: RESOLVED, RESOLVED_FROM_BUILD_OUTPUT, RESOLVED_FROM_PATTERN.
  • A single-* subpath pattern is expanded one path segment at a time, with src/ tried first. This is deliberately narrower than Node, where * can span /.
  • Only package.json files at or under the program root are read.
• engine: projections/packages.dl and a new entry_point kind, package_export, in config-resolution/entry-points.dl.
  • It roots named METHOD exports, and exported variables bound to a function (var_bound_function), of published modules that are not already entry modules.
  • DEFAULT_INDEX entries and entries with no module hash are declined.
• parser: const f = ((x) => …) as F now binds the arrow to f, as a bare arrow already did. The same holds under satisfies, <T>, ! and parentheses. The compiler oracle's labelOf names it the same way.
• Schema, decls, templates, the column-order baseline and SCHEMA.md are updated. The stale "NOT COVERED YET" notes in entry-points.dl are corrected.

Tests

• Golden case 77-package-published-entries covers a build-output main/exports entry, a ./vanilla subpath, a ./plugins/* pattern, an exported arrow and an arrow under as.
• Controls in the same case, each of which must stay unrooted:
  • internal.ts: imported, but named by no entry.
  • a blocked ./internal/*.
  • plugins/deep/tracer.ts: two segments under a one-segment *.
  • DEFAULT_INITIAL and castInitial: values, not functions, including one under as.
• graph/test/typescript/run-tests.sh --oracle: passed 77, failed 0. Case 77 scores oracle=7, engine=8, agree=7, missing=0.
  • The one extra is the function-type signature in the as clause. It is the existing multi-target behaviour for a call through a variable whose declared type is a function type, not a new edge kind.
• graph/test/javascript/run-tests.sh --oracle: passed 68, failed 0. It is affected through the shared package-json resolver and oracle.
• parser suites (npx tsx src/test/{typescript,javascript,csharp,gradle,discovery}-tests.ts): all pass. TypeScript is 47/47, including the column-order gate.

Real projects (before → after)

	methods	call edges	entry_reachable	package_export roots	wall
a real state-management library	1567	1113 → 1294 (+181, 0 lost)	420 → 432	0 → 14	6.3s
a real immutable-update library (control)	487	521 → 521	181 → 181	0 → 13	10.1s

• All 181 new edges on the state-management library go into the as-wrapped createStore / create / createWithEqualityFn arrows. They are calls from its tests that now resolve.
• On the immutable-update library, the 13 new roots were already reached through its tests, so its edges and reach are unchanged.