feat: expose orientation in the Viewer snapshot screen payload

[onevcat]

Summary

Closes #57.

GET /api/snapshot now forwards the CLI's calibrated interface orientation (data.orientation from describe-ui --json, carried since #38) into the screen payload verbatim — no parsing of the (landscape-right) suffix out of the outline text:

{
  "screen": {
    "appLabel": "Safari",
    "width": 874,
    "height": 402,
    "orientation": "landscape-left"
  }
}

• The key is omitted whenever the CLI reports none (Android, legacy daemons), matching the CLI envelope semantics.
• The SPA Screen type gains the optional orientation field, and the toolbar tags a rotated screen next to the W×H readout, e.g. 874×402 (landscape-left). Portrait earns no tag, mirroring the outline header behaviour.

One nuance vs. the issue text: the CLI emits "portrait" (not nil) when calibration resolves upright — only the outline header tag is suppressed for portrait. The handler therefore forwards verbatim (key present iff data.orientation is present) and the portrait suppression lives in the SPA display layer.

Changes

• Sources/SimUse/Viewer/ViewerAPIHandlers.swift — forward data.orientation into the parsed screen dict at the parseScreenFromOutline call site.
• Tools/Viewer/src/types.ts — Screen.orientation?: string (documented canonical values, widened for forward-compat like Device.platform).
• Tools/Viewer/src/App.tsx — rotation tag next to the W×H readout.
• Tests/ViewerAPIHandlersTests.swift — new forwarding case + omitted-key assertion in the existing rotated-outline case.
• CHANGELOG.md, Tools/Viewer/README.md — docs.

Testing

• make build clean, make test passes (1157 tests), tsc -b clean.
• Live spot-check against a booted iPhone 17 Pro (iOS 26.4) via sim-use viewer: portrait Settings reports "orientation": "portrait"; after rotating with Safari foreground the payload flips to "orientation": "landscape-left" with 874×402, byte-consistent with the outline header App: Safari 874x402 (landscape-left).

🤖 Generated with Claude Code

https://claude.ai/code/session_011M3T94iAdsJisr6oH7ynof