fix(cloudflare): adopt durable object classes created outside alchemy

[sam-goodwin]

Cloudflare.Worker already adopts the worker itself, but its Durable Object class migrations only mapped logical-id→class through alchemy:do: tags. A worker created outside Alchemy (raw API, Wrangler, dashboard) has no such tags, so on the adopting deploy every DO class fell into newSqliteClasses — asking Cloudflare to create a class that already exists, which fails the migration.

Fall back to matching the observed cloud binding by binding name (mirrors the original vendor behavior), so an existing class is reused — or renamed if the class name differs — instead of recreated.

let previousClassName = oldDoClassNameByLogicalId[binding.logicalId];
if (!previousClassName) {
  const observed = oldBindings.find(
    (old) => old.type === "durable_object_namespace" &&
             old.className && old.name === binding.bindingName,
  );
  if (observed?.className) previousClassName = observed.className;
}

Limitation (by design): on the adopting deploy the binding's class name must match the existing class. Once Alchemy writes the alchemy:do: tag, later renames are driven by logical id.

Test provisions a worker + Counter SQLite DO class straight through workers.putScript (no Alchemy tags), then deploys an async inline-script Worker over the same name with adopt(true) and round-trips an increment through the reused class. Verified live, alongside the existing class-migration test.

Closes #486

[alchemy-version-bot]

Install the packages built from this commit:

alchemy

bun add alchemy@https://pkg.ing/alchemy/65e518a

@alchemy.run/better-auth

bun add @alchemy.run/better-auth@https://pkg.ing/@alchemy.run/better-auth/65e518a

@alchemy.run/pr-package

bun add @alchemy.run/pr-package@https://pkg.ing/@alchemy.run/pr-package/65e518a

[alchemy-version-bot]

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