feat: native linux-x64-glibc module packages and reviewed license supplements (ADR 0049, ADR 0052)

Implements ADR 0049's deferred native target and ADR 0052's reviewed
license supplements. The proof case is a real module using sharp.
packageFormat stays 1, and `any` is unchanged.

Packager (@ekklesia/module-pack):
- --target linux-x64-glibc. Native or platform-specific packages, found by
  the same generic rule that refuses them in `any`, stay outside the bundle.
- Each native package's production closure is walked through its own
  dependencies, installed optionalDependencies that match the target, and
  required peers. It is copied as real files flat under node_modules/<name>,
  with no links, dev dependencies, declarations, source maps, or other
  platforms' packages. Missing or foreign-platform required dependencies,
  version conflicts, links, foreign machines, and Node.js range conflicts
  fail closed.
- runtime.nodeApi, nodeAbi, and libcVersion are read from the binaries by a
  small ELF reader: the addon's node_api_module_get_api_version_v1 and the
  newest GLIBC_ symbol version needed. No shelling out. A native target with
  no addon is refused.
- ADR 0052 supplements: package-provided material stays primary. An exact
  match on name, version, and ekklesia-content-v1 digest (sorted normalized
  paths with each file's size and SHA-256; no metadata) adds labelled
  material after the package's own. Any mismatch, a declared-licence
  conflict, or a malformed or unreviewed supplement file fails. Missing
  material with no supplement still fails.

Supplement for @img/[email protected]:
- 184 components and 143 unique texts, assembled from the exact upstream
  sources sharp-libvips v1.3.3 builds linux-x64 from: 27 C/C++ libraries,
  glib's gvdb, librsvg's Rust crates (reproduced with cargo tree), the Rust
  standard library at the rustc commit recorded in the binary, plus the
  LGPL-3.0, GPL-3.0, and MPL-2.0 texts. Each source is recorded with its
  SHA-256 in PROVENANCE.md.
- It pins digest ekklesia-content-v1:sha256:50647b0b…, which is identical
  from the installed copy and from the registry tarball.
- LGPL/MPL source-availability determinations stay open, as ADR 0052
  states. Nothing claims they are met.

Verifier (Core):
- linux-x64-glibc is accepted only on a host whose platform, arch, glibc
  family and version, and Node-API version (from Node itself) match.
- Every ELF file must be x86-64; every .node must be an ELF object.
- `any` packages now also refuse node_modules/ and ELF files.
- Contract: native metadata must state nodeApi or nodeAbi, and Linux targets
  libcVersion (ADR 0049).

Proof:
- A checked-in AGPL native fixture packs byte-identically from unrelated
  copies (8.86 MB) and verifies with Core's verifier.
- Extracted elsewhere, it runs a sharp resize and PNG round trip in an
  empty-environment process. Every resolution stays in the package, and
  only the package's addon and libvips plus host system libraries load.

Signage is untouched.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

core/tests/support/module-package-fixture.ts

@@ -94,6 +94,8 @@ export interface PackageFixtureOptions {
   readonly tamper?: (files: Map<string, Buffer>) => void;
   /** Entries appended after the package's own, under any path. */
   readonly extraEntries?: readonly FixtureEntry[];
+  /** Extra payload files, listed in the metadata like every other file. */
+  readonly files?: Readonly<Record<string, Uint8Array | string>>;
 }
 
 export interface PackageFixture {
@@ -163,6 +165,9 @@ export async function modulePackageFixture(
   );
   files.set("THIRD_PARTY_NOTICES", Buffer.from("No third-party software is included.\n"));
   files.set("LICENSE", Buffer.from("Example module license text.\n"));
+  for (const [filePath, data] of Object.entries(options.files ?? {})) {
+    files.set(filePath, Buffer.from(data));
+  }
 
   const listed = [...files.entries()]
     .sort(([left], [right]) => (left < right ? -1 : left > right ? 1 : 0))