release: 1.2.0: Panel 1.2.0-1.2.5: layout, RBAC, tests, GUI and CI fixes

[1.2.0]
The second MINOR after 1.0.0: domain administrators with per-domain scope, a panel visual refresh on the SelfPost palette, and refinements to navigation and the send log. Upgrading runs one SQLite migration (`0005_panel_users`); the single administrator becomes a global user.
Added:
  - panel: **domain-admin role** — global administrators manage panel users and
Fixed:
  - Docker build: `LICENSE` is no longer excluded by `.dockerignore`, so the
  - panel: on signed-in pages with a narrow card (**Settings**, the user form)
Changed:
  - panel: navigation session icons are distinct — **Settings** uses a gear,
  - panel: `/` redirects domain administrators to `/domains`; global users still
  - panel: **Sign out** in the navigation column uses the same type size and
  - panel: **visual style** brought in line with the SelfPost mark — brick accent
  - panel: the send log's **status is a badge**, in the same ok/warn/error/unknown
  … (1 more in CHANGELOG)
[1.2.1]
Panel refinements after 1.2.0: navigation icons, status-badge centreing, drill-down back-link placement, and safeguards for the sole global administrator. Upgrading is a tag bump; no migration.
Fixed:
  - panel: status badge text sat low in the box (and below the heading or label
  - panel: the **Users** navigation icon was two full silhouettes with staggered
  - panel: the **Settings** navigation icon was a sun-with-rays (circle plus
  - panel: the user create/edit form placed «Back to users» at the bottom of the
Changed:
  - panel: the user edit form disables role change and delete for the only global
  - panel: the user create/edit form hides **Assigned domains** when the role is
  - panel: **Settings** shows panel credentials and DMARC aggregate reports side
[1.2.2]
Status page layout after 1.2.1: paired cards in a wide column, denser machine and check copy, and a user-form checkbox fix. Upgrading is a tag bump; no migration.
Changed:
  - panel: **Status** is wide again so paired cards fill the column. Layout:
Fixed:
  - panel: cards inside `.split` used `margin: 0 auto`, which in a CSS grid
  - panel: on the user create/edit form, **Assigned domains** checkboxes stacked
[1.2.3]
Domain detail layout and panel polish after 1.2.2. Upgrading is a tag bump; no migration.
Changed:
  - panel: the domain detail page is wide with paired cards (DKIM+SPF ‖ DMARC;
  - panel: Domains list — **Add domain** sits beside the domain field; the
  - panel: page URLs, browser titles, and headings are aligned — **Settings** is
Fixed:
  - image: `mail.log` rotation no longer silently stops when the build context
[1.2.4]
Level-2 rate-limit semantics inverted after 1.2.3, plus a small DNS field height fix. Upgrading is a tag bump; no migration.
Changed:
  - rate limiting (level 2): domain ceilings apply to every client IP (no IP
Fixed:
  - panel: on the domain DNS status grid, the Type (TXT) field height matches
[1.2.5]
Rate-limit form polish after 1.2.4. Upgrading is a tag bump; no migration.
Changed:
  - panel: rate-limit forms refined — level-1 backstop as muted copy on the

Squashed CHANGELOG sections: [1.2.0], [1.2.1], [1.2.2], [1.2.3], [1.2.4], [1.2.5].

Full detail: CHANGELOG.md (1.2.0, 1.2.1, 1.2.2, 1.2.3, 1.2.4, 1.2.5).

internal/web/auth/principal.go

@@ -0,0 +1,86 @@
+package auth
+
+import (
+	"context"
+	"net/http"
+
+	"github.com/mixeme/selfpost/internal/store"
+)
+
+type ctxKey int
+
+const (
+	usernameKey   ctxKey = 0
+	principalKey  ctxKey = 1
+)
+
+// Role is a panel user's access level.
+type Role = store.Role
+
+const (
+	RoleGlobal      = store.RoleGlobal
+	RoleDomainAdmin = store.RoleDomainAdmin
+)
+
+// Principal is the authenticated panel user attached to a request.
+type Principal struct {
+	ID       int64
+	Username string
+	Role     Role
+	Domains  []int64 // assigned domain IDs; empty for global (all domains)
+}
+
+// IsGlobal reports whether the principal has full panel access.
+func (p Principal) IsGlobal() bool {
+	return p.Role == RoleGlobal
+}
+
+// CanAccessDomain reports whether the principal may access a domain id.
+func (p Principal) CanAccessDomain(domainID int64) bool {
+	if p.IsGlobal() {
+		return true
+	}
+	for _, id := range p.Domains {
+		if id == domainID {
+			return true
+		}
+	}
+	return false
+}
+
+// CanAccessApp reports whether the principal may access an application.
+func (p Principal) CanAccessApp(app store.Application) bool {
+	return p.CanAccessDomain(app.DomainID)
+}
+
+func principalFromUser(u store.User) Principal {
+	return Principal{
+		ID:       u.ID,
+		Username: u.Username,
+		Role:     u.Role,
+		Domains:  u.DomainIDs,
+	}
+}
+
+func withPrincipal(ctx context.Context, p Principal) context.Context {
+	ctx = context.WithValue(ctx, usernameKey, p.Username)
+	return context.WithValue(ctx, principalKey, p)
+}
+
+// CurrentPrincipal returns the authenticated principal from the request context.
+func CurrentPrincipal(ctx context.Context) (Principal, bool) {
+	if v, ok := ctx.Value(principalKey).(Principal); ok {
+		return v, true
+	}
+	return Principal{}, false
+}
+
+// PrincipalFromRequest returns the authenticated principal from an HTTP request.
+func PrincipalFromRequest(r *http.Request) (Principal, bool) {
+	return CurrentPrincipal(r.Context())
+}
+
+// RequestWithPrincipal attaches a principal for middleware-equivalent tests.
+func RequestWithPrincipal(r *http.Request, p Principal) *http.Request {
+	return r.WithContext(withPrincipal(r.Context(), p))
+}