fix(rebase): migrate the replayed E2B branch onto the rebased parent

The linear replay carried old-lineage content over parent-owned files;
this checkpoint restores them and adapts the branch to the parent's
post-rebase seam:

- restore all pty/lsp/subprocess/code-runtime surfaces to the parent's
  exact content (this branch claims none of them) and drop the net-zero
  code-runtime-e2b/pty-e2b/lsp-e2b residue and its registrations
- widen serializeRemoteEnvironment to the seam's NodeJS.ProcessEnv
  tombstone contract: an explicit undefined removes an ambient entry
- migrate the two E2B fixture Agent stubs to the Inbox-model interface
  and Session.create
- re-apply the branch's gen-doc-graphs roles, THIRD_PARTY_NOTICES e2b
  row, and packages/README group row (trimmed to the doc budget);
  regenerate catalogs and re-record bilingual pairings

packages/cordis/tool-cordis/src/api-catalog.ts

@@ -304,6 +304,16 @@ export const SERVICE_API: readonly ServiceApiEntry[] = [
       },
     ],
   },
+  {
+    key: 'e2b',
+    summary: 'Creates one lazily consumable E2B SDK handle and deletes the sandbox at timeout or disposal.',
+    methods: [
+      {
+        signature: 'async getSandbox(): Promise<Sandbox>',
+        jsDoc: '/**\n * Return the shared live SDK handle.\n * @returns the created sandbox after the configured cwd exists.\n * @throws when E2B rejects creation or the service is disposing.\n */',
+      },
+    ],
+  },
   {
     key: 'fs',
     summary: 'Abstract filesystem provider.',