Implement workspace evolution, migrations, and runtime continuity

Enable evolution by default for source-backed workspaces. Add stable
conformance ownership, semantic-major review, candidate typechecking,
and durable fenced cutover with explicit migrations and forward recovery.

Independently supervise package runtimes so unchanged resource owners keep
their processes and connections across cutover. Add scoped invocation
authority, resource sessions, and typed callback rebinding.

Wire opaque object references through generated bindings and RPCs. Add
canonical relationship sets, keyed maps, and ordered lists with scoped
transactional mutations, revision checks, and inverse consistency. Support
planned cascade deletion, protection, tombstones, and lifecycle foundations.

Add journaled structural edits, package/function/migration scaffolding,
managed repository creation, and resumable bottom-up dependency pin
publication. Document lifetime boundaries, revision pinning, prototype
compatibility policy, commands, and deferred work.

Validate with 210 tests, user-systemd process/connection continuity,
generated-package TypeScript checks, and Nix host/protocol checks.
TTL handoff, physical reclamation, general multi-step migrations, and
root-systemd migration isolation acceptance remain deferred.

test/migrations.test.ts

@@ -0,0 +1,36 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { contentDigest, validateMigrationCatalog, selectMigrationPath, type MigrationCatalog } from "../src/capability-model/index.js";
+const before = { fields: ["name"] }, after = { fields: ["first", "last"] };
+const from = contentDigest(before), to = contentDigest(after);
+const catalog = (): MigrationCatalog => ({ schemaVersion: 1, contracts: { [from]: before, [to]: after }, migrations: [{
+  id: "split-name", scopeId: "person-name", from, to,
+  implementation: { exportId: "migrate-name", file: "src/migrate-name.ts", digest: contentDigest("implementation") }, predecessors: [],
+  ports: [{ name: "source", view: "old", access: ["read"], contractDigest: from }, { name: "target", view: "new", access: ["write"], contractDigest: to }],
+}] });
+test("published migrations retain exact old contracts and explicit local bindings", () => {
+  const value = validateMigrationCatalog(catalog(), new Set(["migrate-name"]));
+  const selection = { scopeId: "person-name", from, to, path: ["split-name"], bindings: { source: "old-slot", target: "new-slot" } };
+  const result = selectMigrationPath(value, selection);
+  assert.equal(result[0].alreadyApplied, false);
+  assert.equal(selectMigrationPath(value, selection, new Map([["split-name", result[0].digest]]))[0].alreadyApplied, true);
+  const changed = catalog(); changed.migrations[0].implementation.digest = contentDigest("new code");
+  assert.throws(() => selectMigrationPath(changed, selection, new Map([["split-name", result[0].digest]])), /different code/);
+  assert.throws(() => selectMigrationPath(value, { ...selection, path: [] }), /does not cover/);
+  assert.throws(() => selectMigrationPath(value, { ...selection, bindings: {} }), /Missing local/);
+});
+test("old migration views cannot be writable and contract hashes are verified", () => {
+  const value = catalog(); value.migrations[0].ports[0].access = ["write"];
+  assert.throws(() => validateMigrationCatalog(value), /read-only/);
+  const corrupt = catalog(); corrupt.contracts[from] = {};
+  assert.throws(() => validateMigrationCatalog(corrupt), /digest mismatch/);
+});
+
+test("migration history rejects cycles and non-boolean compatibility promises", () => {
+  const cyclic = catalog();
+  cyclic.migrations[0].predecessors = ["split-name"];
+  assert.throws(() => validateMigrationCatalog(cyclic), /Cyclic/);
+  const misleading = catalog();
+  (misleading.migrations[0] as unknown as {preservesOldReaders: string}).preservesOldReaders = "false";
+  assert.throws(() => validateMigrationCatalog(misleading), /must be booleans/);
+});