Restore a shippable PHP client package after legacy SDK removal

[cferrys]

Summary

The repository is currently in a non-runnable, non-installable state after db64397 removed the legacy SDK classes and autoloader. composer.json, README.md, example.php, and the example scripts still reference deleted runtime files and namespaces, which means the package can no longer be bootstrapped as a PHP client.

Context

The most recent structural change removed the entire lib/ runtime, including lib/Client.php, lib/Request.php, lib/Response.php, and lib/autoload.php, but the package metadata and docs still assume those files exist.

Relevant breakpoints in HEAD:

• composer.json still declares PSR-4 autoloading from lib/ and still includes "lib/autoload.php" in autoload.files.
• README.md still instructs local usage via require_once __DIR__ . '/lib/autoload.php'; and imports Hlquery\Client.
• example.php and all example scripts still require the deleted autoloader path.
• A repository-wide search no longer finds any Hlquery\Client implementation, only helper utilities under utils/.

For a high-performance search engine client, packaging reliability is foundational. If the client cannot be installed or instantiated, users cannot exercise search, vector, SQL, collection, or document APIs at all, and downstream benchmarks or adoption efforts stop at bootstrap.

Proposed Implementation

1. Decide the intended post-removal direction:
   • Restore the maintained client runtime classes into the package, or
   • Publish this repository as utilities/examples only and remove client-package claims.
2. If this repository is still meant to be the PHP client:
   • Reintroduce a supported runtime entrypoint such as Hlquery\Client.
   • Fix composer.json autoload mappings so they reference real paths only.
   • Remove the deleted lib/autoload.php file entry or replace it with a valid bootstrap mechanism.
3. Update all examples and README snippets to use the supported load path and current namespace layout.
4. Add a minimal smoke test in CI that validates:
   • composer dump-autoload succeeds,
   • new Hlquery\Client(...) resolves correctly,
   • one basic request path can be constructed or mocked.
5. Add a release gate that fails if documented bootstrap paths or Composer autoload targets reference missing files.

Impact

Addressing this restores the package’s basic contract: installability, autoload correctness, and a usable client entrypoint. That has the highest leverage because it unblocks every higher-level capability in the project, prevents broken releases, and preserves trust in hlquery as a production-ready interface to a high-performance search/database engine.