feat: multi-tenant company refactor (GNU-19) (#153)

* feat: multi-tenant company refactor (GNU-19)

Introduce companies table, company_members, and user_preferences to
support multiple companies per user. All data scoping changes from
user_id to company_id across the entire codebase.

Key changes:
- Database migration: new tables, company_id on 40+ tables, backfill,
  RLS rewrite from user_id to company-member-based, updated RPCs
- Types: Company, CompanyMember, CompanyRole, UserPreferences types;
  company_id added to all entity interfaces; companyId on all events
- Engine: all 7 core functions take companyId; storno, period, year-end
  services updated; 16 report generators updated
- Middleware: company context resolution (cookie → prefs → first company)
- API routes: ~120 routes updated with requireCompanyId()
- Frontend: CompanyProvider context, layout/dashboard/onboarding updated
- Extensions: context factory, 9 extensions, all lib files updated
- Tests: 1880 tests passing, all helpers updated with company_id defaults

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

* feat: add database migrations for multi-tenant company and team system (GNU-19)

Adds company_invitations, company creation RPC, team_members, account
deletion RPC, and teams table refactor migrations. Updates base
multi-tenant migration with cascading FKs and onboarding_step column.

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

* feat: add team types and update core infrastructure for multi-tenancy (GNU-19)

Adds TeamRole, MemberSource, and Team types. Refactors Supabase service
client to be stateless, updates middleware for team-aware routing, extends
CompanyContext with team/role fields, and updates extension service types
to accept companyId.

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

* refactor: thread company_id through business logic functions (GNU-19)

Replaces user_id scoping with company_id across all lib modules:
bookkeeping, documents, transactions, invoices, reconciliation, tax,
deadlines, and import. Updates corresponding tests.

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

* refactor: thread company_id through API routes and extensions (GNU-19)

Updates all existing API routes to extract and pass companyId. Updates
enable-banking and arcim-migration extensions for company-scoped
transaction ingestion and sync.

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

* feat: add company and team management API routes (GNU-19)

Adds CRUD endpoints for company members, company invitations, team
members, and team invitations. Includes invite token utilities, email
templates, and company switch server action.

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

* feat: add team/company UI components, pages, and dashboard updates (GNU-19)

Adds CompanySwitcher, ConsultantEmptyState, Step0RoleChoice, company
members and team management panels. Updates dashboard layout for
team-aware routing, onboarding for multi-step role choice, and auth
callback for team invite acceptance. Ignores supabase/.branches/.

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

* fix: add null guards for company in import page (GNU-19)

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

* fix: move appUrl declaration to outer scope in invite route (GNU-19)

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

* fix: add optional chaining for company.name in members section (GNU-19)

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

* fix: add optional chaining for second company.name in members section (GNU-19)

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

* fix: add null guards for company in extension components (GNU-19)

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

* fix: pass companyId to executeSIEImport in arcim-migration extension (GNU-19)

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

* fix: update tests to use companyId instead of userId and improve type handling

---------

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

extensions/general/enable-banking/components/BankingSettingsPanel.tsx

@@ -8,6 +8,7 @@ import { useToast } from '@/components/ui/use-toast'
 import { DestructiveConfirmDialog, useDestructiveConfirm } from '@/components/ui/destructive-confirm-dialog'
 import { Loader2, Upload } from 'lucide-react'
 import { createClient } from '@/lib/supabase/client'
+import { useCompany } from '@/contexts/CompanyContext'
 import { BankSelector, type Bank } from './BankSelector'
 import { BankConnectionStatus } from './BankConnectionStatus'
 import type { BankConnection } from '@/types'
@@ -21,6 +22,7 @@ export default function BankingSettingsPanel() {
   const supabase = createClient()
 
   const { dialogProps, confirm } = useDestructiveConfirm()
+  const { company } = useCompany()
 
   const [bankConnections, setBankConnections] = useState<BankConnection[]>([])
   const [syncingConnectionId, setSyncingConnectionId] = useState<string | null>(null)
@@ -38,11 +40,12 @@ export default function BankingSettingsPanel() {
     setIsLoading(true)
     const { data: { user } } = await supabase.auth.getUser()
     if (!user) return
+    if (!company) return
 
     const { data: connections } = await supabase
       .from('bank_connections')
       .select('*')
-      .eq('user_id', user.id)
+      .eq('company_id', company.id)
       .order('created_at', { ascending: false })
 
     setBankConnections(connections || [])