Add WebP quality control and selective visualization (--only / --skip)

- WebP output now uses quality=85 by default (down from lossless),
  reducing file size by ~75% (35MB → 5-8MB per visualization)
- Added --quality N (1-100) and --lossless flags in CLI and run.sh
- Added --only and --skip to select/exclude specific visualizations
  (e.g., --only hillshade,svf,lrm or --skip ortho,topo)
- VIZ_STEPS filtering is done in LidarArchaeoPipeline.__init__
- SharedDEM is skipped when all selected visualizations already exist
- Invalid visualization names are validated at startup with clear error

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

lidar_pipeline/cli.py

@@ -128,6 +128,31 @@ Exemples:
         default="auto",
         help="Méthode de classification du sol : auto (détection), smrf, csf (défaut: auto)"
     )
+    parser.add_argument(
+        "--quality",
+        type=int,
+        default=85,
+        help="Qualité WebP (1-100, défaut: 85). Utilisez 100 pour lossless."
+    )
+    parser.add_argument(
+        "--lossless",
+        action="store_true",
+        help="Forcer la compression WebP lossless (équivalent à --quality 100)"
+    )
+    parser.add_argument(
+        "--only",
+        nargs="+",
+        type=str,
+        default=None,
+        help="Générer uniquement ces visualisations (ex: --only hillshade svf lrm)"
+    )
+    parser.add_argument(
+        "--skip",
+        nargs="+",
+        type=str,
+        default=None,
+        help="Exclure ces visualisations (ex: --skip ortho topo)"
+    )
     parser.add_argument(
         "--file",
         nargs="+",
@@ -168,6 +193,7 @@ Exemples:
     log_gpu_status()
 
     try:
+        quality = 100 if args.lossless else args.quality
         pipeline = LidarArchaeoPipeline(
             input_dir=args.input,
             output_dir=args.output,
@@ -177,6 +203,9 @@ Exemples:
             ground_method=args.ground_classification,
             force_classify=args.force_classification,
             keep_tif=args.keep_tif,
+            quality=quality,
+            only_viz=args.only,
+            skip_viz=args.skip,
         )
 
         # If --file is specified, process only matching files