Add spreadsheet-style home page, migrate full 2026 ledger

- New /lignes route (set as site front page): full line-by-line table of
  every ligne comptable, Vue app with filters (compte/client/type/année)
  and month/year grouping, columns matching the original spreadsheet
  (one per compte). Rows with répartition ≠ montant HT are visibly
  flagged (red row + écart column), not hidden or auto-corrected.
- /dashboard now only holds the aggregate solde-par-compte/par-client view
- Migrated all 199 real 2026 transaction lines + 9 opening balances (from
  REPORT CLOTURE 2025) via a drush import script, preserving raw source
  data (known répartition mismatches included) -- validated with a new
  state-flag bypass of the presave check, used only for historical import
- Added "Autre" as an allowed field_type_ligne value for edge-case rows
- Client taxonomy grew from 15 seeded terms to the full unified list

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

config/sync/field.storage.node.field_type_ligne.yml

@@ -26,6 +26,9 @@ settings:
     -
       value: ouverture
       label: "Ligne d'ouverture"
+    -
+      value: autre
+      label: Autre
   allowed_values_function: ''
 module: options
 locked: false

config/sync/system.site.yml

@@ -8,7 +8,7 @@ slogan: ''
 page:
   403: ''
   404: ''
-  front: /node
+  front: /lignes
 admin_compact_mode: false
 weight_select_max: 100
 default_langcode: en