feat(agent): PublishMiniApp — let the agent publish MiniApps to the market

[bobleer]

Why

When a user has the BitFun Agent build a MiniApp and then says “发布到市场”, the agent had no way to help — the entire submission flow (auth, packaging, upload, submit) was reachable only through the desktop 我的投稿 form. This PR closes that gap end-to-end.

What

New PublishMiniApp agent tool (assembly/core):

• One call publishes an installed app: listing metadata (name/description/icon/tags) comes from meta.json; the local category is mapped onto the market's category set (utility→utilities, dev→developer, game→entertainment, …); the slug is derived from the app name (CJK-safe fallback); the release number and listing id are resolved automatically from the user's submission history.
• Signed-out UX: the tool starts the desktop GitHub auth flow, returns the authorization link for the user to click, and polls in the background so the approval lands in the shared keychain — calling the tool again continues publishing. Pending-review submissions for the same slug are detected and reported instead of double-submitting.
• Takes 1–5 screenshot paths (server requires ≥1); missing screenshots produce actionable guidance instead of a server round-trip.
• Registered across the tool plan / materialization / registry manifests / agent mode allow-lists, with the same permission-prompt pattern as InitMiniApp (publishing still requires the user to approve the tool call).

Shared orchestration (services-integrations::miniapp_market::submit):

• The draft → package → screenshots → submit sequence moves out of the Tauri command into the service crate; the desktop command and the agent tool now share one implementation (desktop handler shrinks by ~64 lines). Progress is mirrored onto the existing miniapp-market-upload-progress event, so an open submissions view displays agent-driven uploads live.

Docs/UI: miniapp-dev skill (both copies) documents the publish flow and its guardrails; tool card metadata added for the chat UI; stale InitMiniApp exposure-doc row corrected (Deferred → Direct).

Testing

• cargo test -p bitfun-services-integrations --features miniapp-market miniapp_market:: — 10 passed (release resolution, slug suggestion, category mapping)
• cargo test -p bitfun-core miniapp_publish — 3 passed; registry:: — 49 passed; modes:: — 10 passed; bitfun-tool-packs — 8 passed
• cargo check -p bitfun-desktop / -p bitfun-core clean; web-ui type-check clean
• Not yet exercised against the production market (needs a signed-in desktop session); suggest one manual publish on a test slug before release.