branding: apply the uploaded logo everywhere and stop the unbranded flash The nav lockup, sign-in wall and brand menu always drew the generated default mark; LogoMark now renders the node's mainLogo branding asset (inline for SVG uploads, an Image otherwise) and the menu copies that SVG. Server side, unparameterised branding reads keyed on the bare broadcaster host while every write used did:web:<host>, so getBranding without a broadcaster parameter (and the linker before it) missed the uploaded assets. Reads now normalise to the DID and fall back to the legacy key. A private node served strangers the raw index.html, skipping the internal-brand meta the client paints from before its fetch lands; they now get the default card, which carries the branding but no stream or profile data. The client also hydrates from its branding cache before refetching, and the page paints the branded background before any script runs. Four chrome color keys (background/foreground per scheme) are registered for the theme work that follows. Claude-Session: https://claude.ai/code/session_014aPQ5yqG9QFxKnbwQfCYKa (cherry picked from commit 204002da18f2b931a6282fa1e62228ab832e8e38)