Refactor: ApplicationContext DI wiring (#131)

* refactor: wire all services through ApplicationContext

- Created src/application_context.py as DI container with TYPE_CHECKING imports
- server.py now instantiates all services in dependency order via ApplicationContext
- Fixed infinite recursion bug: 48 instance methods renamed with underscore prefix
  to avoid shadowing by same-named @classmethod forwarders
- ZeroconfServer: instantiate Zeroconf() in __init__, add _sync_class() to
  configure forwarder, direct _configure/_start calls during wiring
- Config, EngineManager, PreviewManager: all forwarders and _sync_class() intact
- RenderQueue: load_state and subscribe moved to __init__, threading.Lock retained
- DistributedJobManager: subscribe_to_listener moved to __init__

* fix: greedy regex in get_render_devices swallows BlenderKit log output

Changed regex from greedy [\s\S]* to non-greedy .*? with re.DOTALL
so it stops at the first ] (the end of the GPU data JSON array)
instead of matching through timestamped log lines like
[19:36:22.109, __init__.py:2881] that contain trailing brackets.

* fix: AttributeError on .enabled in update_job_count prevents options from rendering

* refactor: log silent AttributeError catches, add _sync_class to remaining services, drop dead ctx slot

src/api/job_import_handler.py

@@ -11,7 +11,7 @@ import requests
 from tqdm import tqdm
 from werkzeug.utils import secure_filename
 
-from distributed_job_manager import DistributedJobManager
+from src.distributed_job_manager import DistributedJobManager
 
 logger = logging.getLogger()