Makima iOS — Screenshots scheme + demo modemakima-ios-m2-auth

Adds an opt-in `Makima-Screenshots` scheme + `Screenshots` build config that
short-circuits auth with an in-process URLProtocol and seeds the app with
canned demo data. Lets us run the app past onboarding in UI tests or on a
fresh simulator without touching a real Makima server.

What lands
- ScreenshotMode: compile-time flag via -DSCREENSHOT_MODE (set in the new
  Screenshots configuration in project.yml).
- AppState: when the flag is on, calls auth.seedScreenshotData() in init.
- AuthStore: adds seedSetClient/seedSetState helpers (internal, only useful
  for screenshot + future preview builds) and a seedScreenshotData that
  wires up a fake APIClient backed by DemoSession.
- DemoSession: URLSession wired to DemoURLProtocol, which answers
  /api/v1/mesh/daemons, /contracts, /mesh/tasks, /directives,
  /listen/sessions, /mesh/tasks/{id}, /mesh/tasks/{id}/output with
  deterministic demo JSON. Host-scoped to makima.jp so production URL
  remains an operational realm.
- Tests/MakimaUITests/ScreenshotTests.swift: five XCTest cases that drive
  the app through Home, Contracts, Task detail, Directives, and Settings.
  Each attaches an XCTAttachment screenshot with a stable name.
- project.yml: adds MakimaUITests target + Screenshots configuration +
  Makima-Screenshots scheme.

Usage (on a Mac)
  make xcgen
  xcodebuild \\
    -project Makima.xcodeproj \\
    -scheme Makima-Screenshots \\
    -configuration Screenshots \\
    -destination 'platform=iOS Simulator,name=iPhone 16 Pro' \\
    test

Screenshots appear as attachments inside the resulting .xcresult bundle;
open the bundle in Xcode > Report Navigator to browse them, or use
`xcrun xcresulttool get test-results attachments` to export to PNG.

Scope
- Normal Debug/Release builds are unaffected — SCREENSHOT_MODE is only
  defined under the Screenshots configuration.
- DemoURLProtocol only matches host=makima.jp, so any real request made
  during screenshot tests (to non-makima.jp hosts) still fails normally.
- No production code path gates on ScreenshotMode beyond the init-time
  seed call; ensureWebSocket is stubbed to a fake online status so the
  masthead pill shows LIVE during screenshots.

Not included in this commit: the matching GitHub Actions workflow
(.github/workflows/ios-ci.yml) — requires a workflow-scoped token to push
and will land as a follow-up. The Swift helper that extracts screenshots
from xcresult is also queued for that follow-up.

1 files changed, 73 insertions, 0 deletions

diff --git a/makima/ios/Tests/MakimaUITests/ScreenshotTests.swift b/makima/ios/Tests/MakimaUITests/ScreenshotTests.swift
new file mode 100644
index 0000000..6d0fba9
--- /dev/null
+++ b/makima/ios/Tests/MakimaUITests/ScreenshotTests.swift
@@ -0,0 +1,73 @@
+import XCTest
+
+/// Driven by CI to capture deterministic screenshots when the app is built
+/// with `-DSCREENSHOT_MODE`. Saves PNGs as XCTest attachments; CI extracts
+/// them from the .xcresult bundle.
+final class ScreenshotTests: XCTestCase {
+    var app: XCUIApplication!
+
+    override func setUp() {
+        super.setUp()
+        continueAfterFailure = false
+        app = XCUIApplication()
+        app.launchArguments += ["-AppleLanguages", "(en)", "-AppleLocale", "en_US"]
+        app.launch()
+    }
+
+    func test01_Home() throws {
+        // Wait for home content to appear
+        let contracts = app.staticTexts["CONTRACTS//"]
+        XCTAssertTrue(contracts.waitForExistence(timeout: 10))
+        snapshot("01-home")
+    }
+
+    func test02_Contracts() throws {
+        let contracts = app.staticTexts["CONTRACTS//"]
+        XCTAssertTrue(contracts.waitForExistence(timeout: 10))
+        contracts.tap()
+        let header = app.staticTexts["CONTRACTS"]
+        _ = header.waitForExistence(timeout: 5)
+        sleep(1)
+        snapshot("02-contracts")
+    }
+
+    func test03_TaskDetail() throws {
+        let recent = app.staticTexts["RECENT TASKS//"]
+        XCTAssertTrue(recent.waitForExistence(timeout: 10))
+        recent.tap()
+        // TasksListView should now be visible
+        let firstTask = app.staticTexts.matching(NSPredicate(format: "label CONTAINS 'HomeStore' OR label CONTAINS 'WebSocket livestream'"))
+            .firstMatch
+        _ = firstTask.waitForExistence(timeout: 5)
+        firstTask.tap()
+        sleep(2)
+        snapshot("03-task-detail")
+    }
+
+    func test04_Directives() throws {
+        let dirs = app.staticTexts["DIRECTIVES//"]
+        XCTAssertTrue(dirs.waitForExistence(timeout: 10))
+        dirs.tap()
+        sleep(1)
+        snapshot("04-directives")
+    }
+
+    func test05_Settings() throws {
+        let gear = app.buttons["Settings"]
+        XCTAssertTrue(gear.waitForExistence(timeout: 10))
+        gear.tap()
+        sleep(1)
+        snapshot("05-settings")
+    }
+
+    // MARK: - Helpers
+
+    /// Adds a screenshot to the test result as an attachment with a stable name.
+    private func snapshot(_ name: String) {
+        let screenshot = XCUIScreen.main.screenshot()
+        let attachment = XCTAttachment(screenshot: screenshot)
+        attachment.name = name
+        attachment.lifetime = .keepAlways
+        add(attachment)
+    }
+}