Translate the whole project to English and fix outdated comments and help

Comments, docstrings, logs, CLI help, map UI, legends, PDF sheet, scripts,
compose files and AGENTS.md are now English. Data keys stay unchanged
(relief_oriente, densite_sol, visualisations/, API JSON keys, link params).
Wrong comments and help defaults found along the way are corrected.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

lidar_pipeline/tests/test_cli.py

@@ -89,10 +89,10 @@ class TestSetupLogging:
 
 
 def test_rebuild_index_without_input_arg(tmp_path):
-    """--rebuild-index fonctionne sans l'argument positionnel input.
+    """--rebuild-index works without the positional input argument.
 
-    Régression : input était obligatoire alors que --rebuild-index ne
-    l'utilise pas (erreur argparse « the following arguments are required »).
+    Regression: input used to be required although --rebuild-index does not
+    use it (argparse error "the following arguments are required").
     """
     import subprocess