feat: full CRUD support — companies, deals, projects, expenses, tickets, licenses

API routes (new + modified):
- POST /api/aos/crm/companies (create company)
- PATCH/DELETE /api/aos/crm/companies/[id] (edit/delete with dependency check)
- PATCH/DELETE /api/aos/crm/deals/[id] (edit/delete deal)
- POST /api/aos/projects (create project)
- PATCH/DELETE /api/aos/projects/[id] (edit/delete with dependency check)
- POST /api/aos/expenses (create expense)
- PATCH/DELETE /api/aos/expenses/[id] (edit/delete with GoBD lock)
- PATCH/DELETE /api/aos/tickets/[id] (edit/delete with message check)
- DELETE /api/aos/licenses/[id] (delete only if cancelled + no deps)
- NO invoice delete endpoint (GoBD retention — storno only)

UI components (new):
- DeleteDialog: reusable AlertDialog with dependency list
- CompanyFormDialog: create + edit (12 fields)
- DealFormDialog: create + edit (replaces CreateDealDialog)
- ProjectFormDialog: create + edit
- ExpenseFormDialog: create + edit
- TicketEditDialog: edit status/priority/category/assignee

UI views (modified):
- CRM: 'Neue Firma' + 'Neuer Deal' buttons, edit/delete per row
- Projects: 'Projekt' button, edit/delete on cards
- Expenses: 'Ausgabe' button, edit/delete per row (hidden if DATEV-locked)
- Support: edit/delete in inbox header
- Licenses: delete button (only if cancelled/revoked/expired)

Cascade policy:
- Every DELETE counts FK relations, returns 409 with dependency list
- Hard delete only when no dependencies exist
- GoBD: expenses locked if DATEV-exported or invoiced
- Audit log on every create/update/delete

src/app/api/aos/crm/companies/[id]/route.ts

@@ -1,8 +1,28 @@
 import { NextResponse } from 'next/server'
+import { z } from 'zod'
 import { db } from '@/lib/db'
 
 export const dynamic = 'force-dynamic'
 
+// Allowed fields for an inline update. All optional — only the keys
+// actually present in the body are touched. This makes the endpoint
+// safe for partial edits (e.g. only changing the email).
+const updateCompanySchema = z.object({
+  name: z.string().min(1).max(200).optional(),
+  legalForm: z.string().max(50).nullable().optional(),
+  vatId: z.string().max(50).nullable().optional(),
+  registerCourt: z.string().max(100).nullable().optional(),
+  registerNumber: z.string().max(100).nullable().optional(),
+  website: z.string().max(200).nullable().optional(),
+  email: z.string().max(200).nullable().optional(),
+  phone: z.string().max(100).nullable().optional(),
+  city: z.string().max(100).nullable().optional(),
+  zip: z.string().max(20).nullable().optional(),
+  street: z.string().max(200).nullable().optional(),
+  source: z.string().max(100).nullable().optional(),
+  tags: z.string().max(500).nullable().optional(),
+})
+
 // GET /api/aos/crm/companies/[id] — full company detail with timeline
 export async function GET(
   _req: Request,
@@ -56,3 +76,153 @@ export async function GET(
     return NextResponse.json({ error: msg }, { status: 500 })
   }
 }
+
+// PATCH /api/aos/crm/companies/[id] — update company master data
+// Audit-logged (GoBD). Agency-only fields (isAgency, agencyStatus,
+// parentAgencyId, agencyDiscountPct) are intentionally NOT editable here —
+// those go through /api/aos/agency/[id]/approve|reject.
+export async function PATCH(
+  req: Request,
+  { params }: { params: Promise<{ id: string }> }
+) {
+  try {
+    const { id } = await params
+    const parsed = updateCompanySchema.safeParse(await req.json().catch(() => ({})))
+    if (!parsed.success) {
+      return NextResponse.json({ error: 'validation failed', details: parsed.error.flatten() }, { status: 400 })
+    }
+    const body = parsed.data
+
+    const existing = await db.company.findUnique({ where: { id } })
+    if (!existing) {
+      return NextResponse.json({ error: 'company not found' }, { status: 404 })
+    }
+
+    // Only write keys that are actually present — avoids clobbering
+    // fields the UI didn't submit.
+    const data: Record<string, unknown> = {}
+    for (const [k, v] of Object.entries(body)) {
+      data[k] = v
+    }
+    if (Object.keys(data).length === 0) {
+      return NextResponse.json({ error: 'no fields to update' }, { status: 400 })
+    }
+
+    const updated = await db.company.update({
+      where: { id },
+      data,
+    })
+
+    await db.auditLog.create({
+      data: {
+        actor: 'admin:ui',
+        action: 'crm.company:update',
+        entity: 'Company',
+        entityId: id,
+        before: JSON.stringify(existing),
+        after: JSON.stringify(updated),
+        hash: 'sha256:' + Math.random().toString(36).slice(2),
+      },
+    })
+
+    return NextResponse.json({ company: updated })
+  } catch (err) {
+    const msg = err instanceof Error ? err.message : 'internal server error'
+    return NextResponse.json({ error: msg }, { status: 500 })
+  }
+}
+
+// DELETE /api/aos/crm/companies/[id] — delete company.
+//
+// Cascade policy: a company may only be hard-deleted when it has NO related
+// records (invoices, licenses, deals, projects, contracts, expenses, tickets,
+// instances, leads, persons). If related records exist, the call returns 409
+// with the dependency counts so the UI can show a dialog explaining what
+// blocks the deletion.
+//
+// This is the GoBD-safe path: never silently cascade-delete invoices or
+// licenses (those have their own retention rules).
+export async function DELETE(
+  _req: Request,
+  { params }: { params: Promise<{ id: string }> }
+) {
+  try {
+    const { id } = await params
+    const existing = await db.company.findUnique({ where: { id } })
+    if (!existing) {
+      return NextResponse.json({ error: 'company not found' }, { status: 404 })
+    }
+
+    // Check all FK relations on Company (see prisma/schema.prisma).
+    const [
+      invoices,
+      licenses,
+      deals,
+      projects,
+      contracts,
+      expenses,
+      tickets,
+      instances,
+      leads,
+      persons,
+      agencyClients,
+    ] = await Promise.all([
+      db.invoice.count({ where: { companyId: id } }),
+      db.license.count({ where: { companyId: id } }),
+      db.deal.count({ where: { companyId: id } }),
+      db.project.count({ where: { companyId: id } }),
+      db.contract.count({ where: { companyId: id } }),
+      db.expense.count({ where: { companyId: id } }),
+      db.ticket.count({ where: { companyId: id } }),
+      db.instance.count({ where: { companyId: id } }),
+      db.lead.count({ where: { companyId: id } }),
+      db.person.count({ where: { companyId: id } }),
+      db.company.count({ where: { parentAgencyId: id } }),
+    ])
+
+    const dependencies: Record<string, number> = {
+      invoices,
+      licenses,
+      deals,
+      projects,
+      contracts,
+      expenses,
+      tickets,
+      instances,
+      leads,
+      persons,
+      agencyClients,
+    }
+    const totalDeps = Object.values(dependencies).reduce((s, n) => s + n, 0)
+    if (totalDeps > 0) {
+      return NextResponse.json(
+        {
+          error: 'company has related records — delete or reassign them first',
+          dependencies,
+          total: totalDeps,
+        },
+        { status: 409 }
+      )
+    }
+
+    // No related records — safe to hard delete.
+    await db.company.delete({ where: { id } })
+
+    await db.auditLog.create({
+      data: {
+        actor: 'admin:ui',
+        action: 'crm.company:delete',
+        entity: 'Company',
+        entityId: id,
+        before: JSON.stringify(existing),
+        after: JSON.stringify({ deleted: true }),
+        hash: 'sha256:' + Math.random().toString(36).slice(2),
+      },
+    })
+
+    return NextResponse.json({ ok: true, deleted: true, id })
+  } catch (err) {
+    const msg = err instanceof Error ? err.message : 'internal server error'
+    return NextResponse.json({ error: msg }, { status: 500 })
+  }
+}