feat: add manual SD card data upload for offline NRLs; rename RecordingSession to MonitoringSession

- Add POST /api/projects/{project_id}/nrl/{location_id}/upload-data endpoint
  accepting a ZIP or multi-file select of .rnd/.rnh files from an SD card.
  Parses .rnh metadata for session start/stop times, serial number, and store
  name. Creates a MonitoringSession (no unit assignment required) and DataFile
  records for each measurement file.

- Add Upload Data button and collapsible upload panel to the NRL detail Data
  Files tab, with inline success/error feedback and automatic file list refresh
  via HTMX after import.

- Rename RecordingSession -> MonitoringSession throughout the codebase
  (models.py, projects.py, project_locations.py, scheduler.py, roster_rename.py,
  main.py, init_projects_db.py, scripts/rename_unit.py). DB table renamed from
  recording_sessions to monitoring_sessions; old indexes dropped and recreated.

- Update all template UI copy from Recording Sessions to Monitoring Sessions
  (nrl_detail, projects/detail, session_list, schedule_oneoff, roster).

- Add backend/migrate_rename_recording_to_monitoring_sessions.py for applying
  the table rename on production databases before deploying this build.

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

scripts/rename_unit.py

@@ -90,14 +90,14 @@ def rename_unit(old_id: str, new_id: str):
         except Exception:
             pass  # Table may not exist
 
-        # Update recording_sessions table (if exists)
+        # Update monitoring_sessions table (if exists)
         try:
             result = session.execute(
-                text("UPDATE recording_sessions SET unit_id = :new_id WHERE unit_id = :old_id"),
+                text("UPDATE monitoring_sessions SET unit_id = :new_id WHERE unit_id = :old_id"),
                 {"new_id": new_id, "old_id": old_id}
             )
             if result.rowcount > 0:
-                print(f"  ✓ Updated recording_sessions ({result.rowcount} rows)")
+                print(f"  ✓ Updated monitoring_sessions ({result.rowcount} rows)")
         except Exception:
             pass  # Table may not exist