feat(landing): establish a fork-owned Marka landing site

[absolutepraya]

Goal

Turn the landing application into the public, fork-owned Marka landing site. It must communicate Marka’s product identity, reflect the maintained fork, and avoid presenting upstream Karakeep infrastructure as if it were operated by this repository.

Relationship

• Parent identity work: feat: rebrand the fork with a one-word product identity #10
• Documentation alignment: docs: establish coherent documentation and assistant context #11
• This issue intentionally follows the Phase 1 asset and product-identity work.

Scope

• Apply the approved Marka name, navy and white visual system, logo derivatives, favicon, social image, page title, and metadata throughout apps/landing.
• Rewrite landing copy, navigation, calls to action, screenshots, and product positioning for the fork.
• Replace upstream-owned links with fork-owned destinations where available. Retain upstream attribution only where it is accurate and intentional.
• Define the hosting, canonical URL, analytics, social-card, and preview-deployment model before public cutover.
• Audit legal, pricing, cloud, demo, app-store, and extension claims. Remove or clearly qualify any upstream-operated surface not provided by this fork.
• Update repository-facing previews and screenshots when the public landing design is approved.

Guardrails

• Do not change DNS, production hosting, OAuth, analytics, or redirects without a separate reviewed cutover plan and explicit approval.
• Preserve upstream attribution and avoid implying ownership of upstream services.
• Keep internal Karakeep-compatible package names and identifiers unless a separately approved migration covers compatibility.

Acceptance criteria

• The landing site consistently presents Marka as this fork’s public identity.
• User-visible assets, metadata, and social cards use the approved Marka PNG asset set.
• Copy and links accurately distinguish this fork from upstream Karakeep and upstream-operated services.
• A reviewed deployment and domain plan exists before publishing.
• Desktop and mobile views, links, metadata, and build checks are verified.

[absolutepraya]

Audit 2026-08-22: valid and still actionable. The landing app exists, but it is still upstream-facing: apps/landing/src/pages/index.astro:12-14 uses Karakeep and karakeep.app, src/constants.ts:1-4 points at the upstream repository, docs, demo, and cloud, and src/layouts/BaseLayout.astro:11-18 uses the upstream canonical URL and metadata. This is not a core application outage, so severity:medium reflects an important public identity and trust gap. Keep the implementation focused on fork-owned branding, links, claims, and a reviewed deployment plan.