chore: sync the frontend template from 4dc033c to 8157ad4

The product was materialized from the template at `4dc033c` and has stayed
on it through 43 template commits, so it was missing all three rounds of
adapter remediation — including files it never had, such as the shared
`abortable-operation` primitive and the `exact-snapshot` decoder that
later fixes are written against. Taking only the newest round was not
possible for that reason: the delta is coherent only as a whole.

The product had not touched `src/adapters` at all since materialization,
so the 140-file delta applied with a three-way merge and no conflicts.
`package.json` was the single overlap and merged cleanly: the product owns
`name`, the template contributed `check:adapter-inventory`,
`check:remediation-ledger` and the image-resolve-signal type fixture.
All 24 product-owned files — README, index.html, CI workflow, i18n
catalog, home page, generated schemas, evidence scripts, component and
visual snapshots — are byte-identical to `main`.

`template.lock.json` now pins the synced revision and tree.

Verified in this repository, not inherited from the template: six type
projects, lint, nine gates (adapter inventory, remediation ledger,
registries, diagnostics, realtime boundaries, architecture, browser
file/storage boundaries, optional recipes, documentation), the production
build, and 2,054 of 2,073 tests. The 19 failures are all in
`tests/unit/ci-artifact-contract.test.ts` and are the same pre-existing
sandbox RLIMIT, EMFILE, umask and `/tmp` permission behaviour the template
records; four suites that failed once under parallel load pass in
isolation.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

scripts/lib/fixture-node-modules.ts

@@ -0,0 +1,31 @@
+import { lstat, mkdir, readdir, symlink } from "node:fs/promises";
+import path from "node:path";
+
+/**
+ * Links the repository's installed dependencies into a throwaway fixture root.
+ *
+ * The obvious form — one directory symlink at `<fixture>/node_modules` — is
+ * destructive. A fixture runs `pnpm` inside itself, pnpm does not recognise the
+ * modules directory it finds there, and its purge follows the symlink and
+ * deletes the *repository's* real dependencies mid-run. With `CI=true` that
+ * happens without a prompt, so a test suite silently uninstalls the workspace
+ * it is running in.
+ *
+ * `node_modules` is therefore a real directory here, and every entry inside it
+ * is an individual symlink. Package resolution is unchanged, but a recursive
+ * delete unlinks the fixture's own symlinks instead of walking through one link
+ * into the shared tree.
+ */
+export async function linkFixtureNodeModules(
+  fixtureRoot: string,
+  sourceRoot: string = process.cwd(),
+): Promise<void> {
+  const source = path.join(sourceRoot, "node_modules");
+  const target = path.join(fixtureRoot, "node_modules");
+  await mkdir(target, { recursive: true });
+  for (const entry of await readdir(source)) {
+    const from = path.join(source, entry);
+    const stats = await lstat(from);
+    await symlink(from, path.join(target, entry), stats.isDirectory() ? "dir" : "file");
+  }
+}