Replace batch DAG system with streaming architecture

- Remove legacy_tasks.py, hybrid_state.py, render.py
- Remove old task modules (analyze, execute, execute_sexp, orchestrate)
- Add streaming interpreter from test repo
- Add sexp_effects with primitives and video effects
- Add streaming Celery task with CID-based asset resolution
- Support both CID and friendly name references for assets
- Add .dockerignore to prevent local clones from conflicting

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

sexp_effects/__init__.py

@@ -0,0 +1,32 @@
+"""
+S-Expression Effects System
+
+Safe, shareable effects defined in S-expressions.
+"""
+
+from .parser import parse, parse_file, Symbol, Keyword
+from .interpreter import (
+    Interpreter,
+    get_interpreter,
+    load_effect,
+    load_effects_dir,
+    run_effect,
+    list_effects,
+    make_process_frame,
+)
+from .primitives import PRIMITIVES
+
+__all__ = [
+    'parse',
+    'parse_file',
+    'Symbol',
+    'Keyword',
+    'Interpreter',
+    'get_interpreter',
+    'load_effect',
+    'load_effects_dir',
+    'run_effect',
+    'list_effects',
+    'make_process_frame',
+    'PRIMITIVES',
+]