panel-redesign: the 2.0 schema from zero - one baseline, no 1.x chain

Stage 1, step 1. BREAKING: a 1.x database is not migrated.

Schema
  - internal/store/migrations/ holds one file, 0001_init.sql, equal to the
    2.0 schema; 0002..0010 are deleted (they stay in history at 1.9.5). No
    admin table created and dropped, no ALTERs.
  - users.email replaces users.dmarc_report_email: the address is the
    user's own. The default DMARC report address is a user's setting
    (dmarc_default_mode hosted/account/custom/none, dmarc_default_address);
    the instance setting that mirrored the global user's field is gone.
  - domains.dmarc_rua_user_id: a domain follows a named user's default, or
    has an address of its own in dmarc_rua ('' = none). ON DELETE SET NULL
    leaves it at "no reports", never at someone else's default.
  - user_inbound_domains, users.all_domains, users.all_inbound_domains: in
    the schema for the inbound delegation of the next step.
  - users.role is 'global' / 'domain' (was 'domain_admin');
    rate_limits.allowed_ips, unused since 1.9.0, is dropped.

Opening a database
  - The baseline sets PRAGMA application_id ("SP20"). store.Open refuses a
    file that has a schema version without it (ErrForeignSchema) and one
    newer than the build. A 1.x file at user_version 10 would otherwise read
    as already migrated. The refused file is left untouched.

Code
  - Store.DomainDMARCRua is the one place a domain's report address is
    resolved; dnscheck.ResolveDMARCRua and Store.GlobalDMARCReportEmail are
    gone. dmarc.AllowedRecipients, the domain page, the dashboard and the
    DNS re-check go through it.
  - The old templates keep working on the new model until their pages are
    restyled: the Settings form's address field is the account e-mail and
    switches the user's default between it and none; a domain's "Same as
    Settings" makes it follow the user who chose it; a new or imported
    domain follows its creator.
  - Domain export/import: a domain that follows a user exports no address.

Tests: the baseline pinned table by table (TestBaselineSchema), refusal of a
1.x and of a newer database, constraints and cascades of the new columns and
table, resolution in every default mode, the deleted-user case, and the three
bridged handlers.

docs/schema-migrations.md is rewritten for the baseline; roadmap 11/27,
schema-squash marked built.

go test ./...   (Windows)
  ok for every package except two that fail the same way before this commit:
  internal/domain  TestWriteLoadPrivateKeyRoundtrip (file mode on NTFS)
  internal/logtail TestFollowTailsAndRotates (rename of an open file)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/web/handlers/handlers_users.go

@@ -58,7 +58,7 @@ func (h *Handlers) HandleUserNew(w http.ResponseWriter, r *http.Request) {
 	}
 	switch r.Method {
 	case http.MethodGet:
-		h.renderUserForm(w, r, http.StatusOK, 0, userFormView{FormRole: string(store.RoleDomainAdmin)})
+		h.renderUserForm(w, r, http.StatusOK, 0, userFormView{FormRole: string(store.RoleDomain)})
 	case http.MethodPost:
 		h.submitUserCreate(w, r)
 	default:
@@ -162,11 +162,11 @@ func (h *Handlers) submitUserCreate(w http.ResponseWriter, r *http.Request) {
 		h.renderUserForm(w, r, http.StatusBadRequest, 0, userFormView{FormErr: err.Error(), FormUsername: username, FormRole: string(role), FormDomains: domainIDSetFromForm(r)})
 		return
 	}
-	if role != store.RoleGlobal && role != store.RoleDomainAdmin {
+	if role != store.RoleGlobal && role != store.RoleDomain {
 		h.renderUserForm(w, r, http.StatusBadRequest, 0, userFormView{FormErr: "Choose a valid role.", FormUsername: username, FormRole: string(role), FormDomains: domainIDSetFromForm(r)})
 		return
 	}
-	if role == store.RoleDomainAdmin && len(domainIDs) == 0 {
+	if role == store.RoleDomain && len(domainIDs) == 0 {
 		h.renderUserForm(w, r, http.StatusBadRequest, 0, userFormView{FormErr: "Select at least one domain for a domain administrator.", FormUsername: username, FormRole: string(role), FormDomains: domainIDSetFromForm(r)})
 		return
 	}
@@ -213,16 +213,16 @@ func (h *Handlers) submitUserUpdate(w http.ResponseWriter, r *http.Request, u st
 		h.renderUserForm(w, r, http.StatusBadRequest, u.ID, userFormView{FormErr: err.Error(), FormUsername: username, FormRole: string(role), FormDomains: selected})
 		return
 	}
-	if role != store.RoleGlobal && role != store.RoleDomainAdmin {
+	if role != store.RoleGlobal && role != store.RoleDomain {
 		h.renderUserForm(w, r, http.StatusBadRequest, u.ID, userFormView{FormErr: "Choose a valid role.", FormUsername: username, FormRole: string(role), FormDomains: selected})
 		return
 	}
-	if role == store.RoleDomainAdmin && len(domainIDs) == 0 {
+	if role == store.RoleDomain && len(domainIDs) == 0 {
 		h.renderUserForm(w, r, http.StatusBadRequest, u.ID, userFormView{FormErr: "Select at least one domain for a domain administrator.", FormUsername: username, FormRole: string(role), FormDomains: selected})
 		return
 	}
 
-	if u.Role == store.RoleGlobal && role == store.RoleDomainAdmin {
+	if u.Role == store.RoleGlobal && role == store.RoleDomain {
 		n, err := h.store.CountGlobalUsers()
 		if err != nil || n <= 1 {
 			msg := "Cannot demote the last global administrator."
@@ -249,7 +249,7 @@ func (h *Handlers) submitUserUpdate(w http.ResponseWriter, r *http.Request, u st
 		hash = string(newHash)
 	}
 
-	if err := h.store.UpdateUser(u.ID, username, hash, u.DMARCReportEmail); err != nil {
+	if err := h.store.UpdateUser(u.ID, username, hash, u.Email); err != nil {
 		if errors.Is(err, store.ErrUserExists) {
 			h.renderUserForm(w, r, http.StatusConflict, u.ID, userFormView{FormErr: "That username is already in use.", FormUsername: username, FormRole: string(role), FormDomains: selected})
 			return
@@ -272,7 +272,7 @@ func (h *Handlers) submitUserUpdate(w http.ResponseWriter, r *http.Request, u st
 		}
 	}
 
-	if role == store.RoleDomainAdmin {
+	if role == store.RoleDomain {
 		if err := h.store.SetUserDomains(u.ID, domainIDs); err != nil {
 			logf("panel: set user domains: %v", err)
 			h.renderUserForm(w, r, http.StatusInternalServerError, u.ID, userFormView{FormErr: "Could not save domain assignments.", FormUsername: username, FormRole: string(role), FormDomains: selected})