feat: remove AI extensions, restructure settings, and add atomic voucher commits (#157)

Remove AI-dependent extensions (ai-chat, ai-categorization, receipt-ocr,
invoice-inbox) and their infrastructure (lib/ai/*, ai-consent, LangChain/
Anthropic/OpenAI deps) to simplify core and reduce bundle size.

Restructure monolithic settings page into dedicated sub-pages (company,
bookkeeping, invoicing, tax, banking, api, account, team, templates) with
shared layout and sidebar navigation.

Add atomic commit_journal_entry RPC so voucher number increment and status
update happen in a single transaction — prevents burned numbers on constraint
failures. Add continuity check report and voucher gap explanation tracking.

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/helpers.ts

@@ -516,6 +516,15 @@ export function makeCompanySettings(
     next_delivery_note_number: 1,
     invoice_default_days: 30,
     invoice_default_notes: null,
+    bookkeeping_locked_through: null,
+    auto_lock_period_days: null,
+    ore_rounding: true,
+    invoice_show_ocr: true,
+    invoice_show_bankgiro: true,
+    invoice_show_plusgiro: true,
+    invoice_late_fee_text: null,
+    invoice_credit_terms_text: null,
+    logo_url: null,
     onboarding_step: 6,
     onboarding_complete: true,
     sector_slug: null,