Add team-only user creation, remove public signup

- Add + New User form on Companies page (name, email, password, company)
- Create-user Supabase edge function with role verification
- Remove public signup route and login page link

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

supabase/functions/create-user/index.ts

@@ -0,0 +1,65 @@
+// deno-lint-ignore-file
+import { serve } from 'https://deno.land/std@0.168.0/http/server.ts'
+import { createClient } from 'https://esm.sh/@supabase/supabase-js@2'
+
+const corsHeaders = {
+  'Access-Control-Allow-Origin': '*',
+  'Access-Control-Allow-Headers': 'authorization, x-client-info, apikey, content-type',
+}
+
+const ok = (body: Record<string, unknown>) => new Response(JSON.stringify(body), {
+  status: 200,
+  headers: { ...corsHeaders, 'Content-Type': 'application/json' },
+})
+
+serve(async (req) => {
+  if (req.method === 'OPTIONS') return new Response('ok', { headers: corsHeaders })
+
+  try {
+    const authHeader = req.headers.get('Authorization') ?? ''
+    if (!authHeader) return ok({ error: 'No authorization header' })
+
+    const callerClient = createClient(
+      Deno.env.get('SUPABASE_URL') ?? '',
+      Deno.env.get('SUPABASE_ANON_KEY') ?? '',
+      { global: { headers: { Authorization: authHeader } } }
+    )
+
+    const { data: userData, error: userError } = await callerClient.auth.getUser()
+    if (userError || !userData?.user) return ok({ error: `Auth failed: ${userError?.message ?? 'no user'}` })
+
+    const { data: profile, error: profileError } = await callerClient
+      .from('profiles').select('role').eq('id', userData.user.id).single()
+    if (profileError) return ok({ error: `Profile error: ${profileError.message}` })
+    if (profile?.role !== 'team') return ok({ error: 'Forbidden: team only' })
+
+    const body = await req.json()
+    const { name, email, password, company_id } = body
+    if (!name || !email || !password) return ok({ error: 'name, email and password are required' })
+
+    const admin = createClient(
+      Deno.env.get('SUPABASE_URL') ?? '',
+      Deno.env.get('SUPABASE_SERVICE_ROLE_KEY') ?? ''
+    )
+
+    const { data: created, error: createError } = await admin.auth.admin.createUser({
+      email,
+      password,
+      email_confirm: true,
+      user_metadata: { name, role: 'client' },
+    })
+
+    if (createError) return ok({ error: `Create user failed: ${createError.message}` })
+
+    if (company_id && created?.user) {
+      const { error: assignError } = await admin
+        .from('profiles').update({ company_id }).eq('id', created.user.id)
+      if (assignError) return ok({ error: `User created but company assign failed: ${assignError.message}` })
+    }
+
+    return ok({ success: true })
+
+  } catch (err) {
+    return ok({ error: `Unexpected: ${String(err)}` })
+  }
+})