[Distribution] Website download page (link Releases + verify steps)

[chtnnh]

Parent

Part of #79 (app distribution). Depends on #61 (site hosting) and Android Releases.

Summary

website/src/content/docs/get-started.mdx still says there is no download page and users must build from GitHub. Trust copy (“only install a build you compiled yourself, or one from a source you trust”) is already on the splash and responsibility pages (#64) — this issue is only the install/download UX.

Why it matters

Once Cloudflare Pages (#61) is live, the first question visitors ask is “where do I get the APK?” Without a page, the guide dead-ends on source builds.

Proposed direction

• Add a short Download / Install page (or expand get-started): platform, version, link to GitHub Release, SHA-256 verify steps in plain language
• Do not weaken trust copy; point at the same “prefer a build you trust” language
• Prefer linking Releases over hosting large binaries on Pages (unless [Docs] Host and publish the user guide (Cloudflare Pages / domain) #61 decides otherwise)

Done when

• Public site has a clear Android install path (and honest iOS status)
• Checksum verification is explained for non-experts
• get-started no longer only says “build from source” once Releases exist
• README links the live download URL (after [Docs] Host and publish the user guide (Cloudflare Pages / domain) #61)

Related

#61 hosting, Releases + signing children of #79, #11 content (mostly done).