Add generic streaming interpreter with configurable sources/audio

- Add stream_sexp_generic.py: fully generic sexp interpreter
- Add streaming primitives for video sources and audio analysis
- Add config system for external sources and audio files
- Add templates for reusable scans and macros
- Fix video/audio stream mapping in file output
- Add dynamic source cycling based on sources array length
- Remove old Python effect files (migrated to sexp)
- Update sexp effects to use namespaced primitives

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

configs/audio-dizzy.sexp

@@ -0,0 +1,17 @@
+;; Audio Configuration - dizzy.mp3
+;;
+;; Defines audio analyzer and playback for a recipe.
+;; Pass to recipe with: --audio configs/audio-dizzy.sexp
+;;
+;; Provides:
+;;   - music: audio analyzer for beat/energy detection
+;;   - audio-playback: path for synchronized playback
+
+(require-primitives "streaming")
+
+;; Audio analyzer (provides beat detection and energy levels)
+;; Paths relative to working directory (project root)
+(def music (streaming:make-audio-analyzer "dizzy.mp3"))
+
+;; Audio playback path (for sync with video output)
+(audio-playback "dizzy.mp3")