feat: Add quality-based CDM selection for dynamic CDM switching

Implements dynamic CDM selection based on video track resolution to optimize
CDM usage. Automatically selects appropriate security level (L3/SL2K for ≤1080p, L1/SL3K for >1080p) based on content requirements.

Key Features:
- Quality-based CDM configuration with threshold operators (>=, >, <=, <)
- Pre-selection based on highest quality across all video tracks
- Maintains backward compatibility with existing CDM configurations
- Single CDM per session to avoid inefficient switching

unshackle/unshackle-example.yaml

@@ -88,6 +88,26 @@ cdm:
     jane_uhd: nexus_5_l1 # Profile 'jane_uhd' uses Nexus 5 L1
     default: generic_android_l3 # Default CDM for this service
 
+  # NEW: Quality-based CDM selection
+  # Use different CDMs based on video resolution
+  # Supports operators: >=, >, <=, <, or exact match
+  EXAMPLE_QUALITY:
+    "<=1080": generic_android_l3 # Use L3 for 1080p and below
+    ">1080": nexus_5_l1 # Use L1 for above 1080p (1440p, 2160p)
+    default: generic_android_l3 # Optional: fallback if no quality match
+
+  # You can mix profiles and quality thresholds in the same service
+  NETFLIX:
+    # Profile-based selection (existing functionality)
+    john: netflix_l3_profile
+    jane: netflix_l1_profile
+    # Quality-based selection (new functionality)
+    "<=720": netflix_mobile_l3
+    "1080": netflix_standard_l3
+    ">=1440": netflix_premium_l1
+    # Fallback
+    default: netflix_standard_l3
+
 # Use pywidevine Serve-compliant Remote CDMs
 remote_cdm:
   - name: "chrome"
@@ -106,16 +126,16 @@ remote_cdm:
     secret: secret_key
 
   - name: "decrypt_labs_chrome"
-    type: "decrypt_labs"  # Required to identify as DecryptLabs CDM
-    device_name: "ChromeCDM"  # Scheme identifier - must match exactly
+    type: "decrypt_labs" # Required to identify as DecryptLabs CDM
+    device_name: "ChromeCDM" # Scheme identifier - must match exactly
     device_type: CHROME
     system_id: 4464 # Doesn't matter
     security_level: 3
     host: "https://keyxtractor.decryptlabs.com"
-    secret: "your_decrypt_labs_api_key_here"  # Replace with your API key
+    secret: "your_decrypt_labs_api_key_here" # Replace with your API key
   - name: "decrypt_labs_l1"
     type: "decrypt_labs"
-    device_name: "L1"  # Scheme identifier - must match exactly
+    device_name: "L1" # Scheme identifier - must match exactly
     device_type: ANDROID
     system_id: 4464
     security_level: 1
@@ -124,7 +144,7 @@ remote_cdm:
 
   - name: "decrypt_labs_l2"
     type: "decrypt_labs"
-    device_name: "L2"  # Scheme identifier - must match exactly
+    device_name: "L2" # Scheme identifier - must match exactly
     device_type: ANDROID
     system_id: 4464
     security_level: 2
@@ -133,7 +153,7 @@ remote_cdm:
 
   - name: "decrypt_labs_playready_sl2"
     type: "decrypt_labs"
-    device_name: "SL2"  # Scheme identifier - must match exactly
+    device_name: "SL2" # Scheme identifier - must match exactly
     device_type: PLAYREADY
     system_id: 0
     security_level: 2000
@@ -142,7 +162,7 @@ remote_cdm:
 
   - name: "decrypt_labs_playready_sl3"
     type: "decrypt_labs"
-    device_name: "SL3"  # Scheme identifier - must match exactly
+    device_name: "SL3" # Scheme identifier - must match exactly
     device_type: PLAYREADY
     system_id: 0
     security_level: 3000