feat(keycloak): M4.3 — Admin API adapter + claim resolver

internal/keycloak/ — Adapter interface with two implementations:
  HTTPAdapter  cached client-credentials token; CreateOrgAndInvite +
               SyncClaims + Health against the real KC Admin API.
  Mock         in-process map for unit tests + dev convenience when
               KEYCLOAK_ADMIN_URL is empty. Used by the eachStore harness.

POST /v1/tenants now accepts admin_email + admin_name. When set, the
adapter creates a KC organization, invites the user as IT_ADMIN, and
triggers VERIFY_EMAIL + UPDATE_PASSWORD. Response wraps the tenant
with TenantCreated{tenant, invite_url}. KC failures DO NOT roll the
tenant back — they emit a keycloak.provision_failed audit event.
Successful invites emit keycloak.invite_sent.

POST /v1/internal/keycloak/claims resolves a tenant's current claim
bundle (tenant_id, slug, products, plan, status). Lookup chain:
body.tenant_id → body.tenant_slug → user_attrs.tenant_id →
user_attrs.tenant_slug.

Config: KEYCLOAK_ADMIN_URL / REALM / CLIENT_ID / CLIENT_SECRET;
empty URL falls back to Mock.

Tests:
  internal/keycloak/mock_test.go     conflict surfacing, FailNext hook,
                                     SyncClaims persistence.
  internal/keycloak/client_test.go   HTTPAdapter against an in-process
                                     stub KC: health, full create-org-
                                     and-invite, conflict, token-cache,
                                     401 retry, ErrUnavailable.
  internal/server/keycloak_test.go   eachStore integration: provisions
                                     via mock; failure path emits
                                     provision_failed audit; claims
                                     endpoint via every lookup variant
                                     + 404 + 400.

OpenAPI extended with TenantCreated + Claims schemas and the new
claims endpoint. Contract test asserts the new path.

CI: include internal/keycloak/... in the test package list so
HTTPAdapter coverage counts. Total project line coverage: 71.6%.

Refs: M4.3

internal/server/tenants.go

@@ -20,6 +20,18 @@ type createTenantReq struct {
 	Plan       string `json:"plan,omitempty"`
 	Kind       string `json:"kind,omitempty"`
 	SalesOwner string `json:"sales_owner,omitempty"`
+	// AdminEmail is optional. When set, the Keycloak adapter provisions
+	// an organization + invites this user as IT_ADMIN. Omitted for
+	// sales-led flows that invite the admin later via the portal.
+	AdminEmail string `json:"admin_email,omitempty"`
+	AdminName  string `json:"admin_name,omitempty"`
+}
+
+// createTenantResp wraps the tenant with the optional KC invite URL so
+// dev testers can use it without waiting for the email.
+type createTenantResp struct {
+	Tenant    *store.Tenant `json:"tenant"`
+	InviteURL string        `json:"invite_url,omitempty"`
 }
 
 func (s *Server) createTenant(w http.ResponseWriter, r *http.Request) {
@@ -40,7 +52,7 @@ func (s *Server) createTenant(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	ctx, cancel := context.WithTimeout(r.Context(), 5*time.Second)
+	ctx, cancel := context.WithTimeout(r.Context(), 10*time.Second)
 	defer cancel()
 	t, err := s.Store.CreateTenant(ctx, store.TenantCreate{
 		Slug: in.Slug, Name: in.Name, Plan: in.Plan, Kind: in.Kind, SalesOwner: in.SalesOwner,
@@ -63,7 +75,25 @@ func (s *Server) createTenant(w http.ResponseWriter, r *http.Request) {
 		Metadata:   map[string]interface{}{"plan": t.Plan, "kind": t.Kind},
 	})
 
-	writeJSON(w, http.StatusCreated, t)
+	// Best-effort Keycloak provisioning. A failure here doesn't roll the
+	// tenant back — the operator can resend the invite via the KC admin UI.
+	// We emit an audit event regardless so the failure is traceable.
+	inviteURL, kcErr := s.provisionKeycloak(ctx, t, in.AdminEmail, in.AdminName)
+	if kcErr != nil {
+		s.emitAudit(ctx, r, store.AuditEvent{
+			TenantID: t.ID, Action: "keycloak.provision_failed",
+			TargetID: t.ID, TargetType: "tenant",
+			Metadata: map[string]interface{}{"err": kcErr.Error(), "admin_email": in.AdminEmail},
+		})
+	} else if in.AdminEmail != "" {
+		s.emitAudit(ctx, r, store.AuditEvent{
+			TenantID: t.ID, Action: "keycloak.invite_sent",
+			TargetID: in.AdminEmail, TargetType: "user", TargetName: in.AdminEmail,
+			Metadata: map[string]interface{}{"role": "IT_ADMIN"},
+		})
+	}
+
+	writeJSON(w, http.StatusCreated, createTenantResp{Tenant: t, InviteURL: inviteURL})
 }
 
 func (s *Server) getTenant(w http.ResponseWriter, r *http.Request) {