Config: Update flow ratios to calibrated value (1.00 for PLA)

- Orca PLA profiles (Bambu + Original): flow_ratio 0.98 → 1.00
- Calibrated via Orca Flow Test on 2026-03-14
- Other filaments (PETG, ABS, TPU) keep default values pending calibration

- user_settings_clean.cfg: Added _FILAMENT_SETTINGS macro
  - cleaning_temperatures for KNCM (PLA:140, PETG:160, TPU:180, ABS:190)
  - flow_ratios (PLA:1.00 calibrated, others default)
  - pressure_advance defaults per hotend type
  - retraction defaults per hotend type

orca-profiles/Neptune4Plus-Original/filament_pla_original.json

@@ -82,7 +82,7 @@
     "filament_is_support": 0,
     "filament_soluble": 0,
     "filament_dissolve_interval": 0,
-    "filament_flow_ratio": 0.98,
+    "filament_flow_ratio": 1.00,
     "filament_max_speed": 0,
     "filament_minimal_purge_on_wipe_tower": 15,
     "filament_pressure_advance": 0.050,
@@ -140,7 +140,7 @@
     "filament_spool_weight": 0,
     "filament_diameter": 1.75,
     "filament_max_volumetric_speed": 15.0,
-    "filament_flow_ratio": 0.98,
+    "filament_flow_ratio": 1.00,
     "filament_max_speed": 0,
     "filament_minimal_purge_on_wipe_tower": 15,
     "filament_pressure_advance": 0.050,