[JJC-20260618-005-D] P1/P2 cleanup: structured errors, privacy audit, timeout SSOT, view-model tests

13 items, 555-line diff, build + 15/15 tests green.

ARCH-A3: Phase.error now carries ErrorKind (micDenied/speechDenied/asr/llm/
appGroupUnavailable/unknown) so the UI can pick icons/copy without parsing
free-form strings. Phase.ErrorKind, Phase, LLMError all Equatable.

ARCH-A4: Every TextField in APISettingsCard gets .keyboardType(.asciiCapable)
to defeat SwiftUI's iOS 18 system-keyboard hand-off that auto-suggests
Chinese/emoji and corrupts API keys / URLs / model names.

ARCH-A5 + DOC-3: PrivacyInfo.xcprivacy audited for honesty. Removed three
declared-but-unused APIs (FileTimestamp / DiskSpace / SystemBootTime) and
added ActiveKeyboards (DDA9.1) to the extension (it actually calls
advanceToNextInputMode in the tap path). Main App now declares only
UserDefaults (CA92.1). CHANGELOG updated.

ARCH-A6: Extracted PermissionManager (mic+speech permission flow, iOS 17
branching) and AppGroupPersistor (App Group load/persist) from the God
Object. KeyboardViewController drops 515 → 459 lines. KeyboardPipelineController
left in-place per risk plan — pressBegan state machine is too race-sensitive
to refactor in this pass.

RED-2: Deleted unused Theme enum (no call sites).
RED-3: Deleted unused cardStyle() alias (no call sites).
RED-7: Single source of truth for LLM timeout — LLMClient.requestTimeout +
LLMClientFactory.defaultRequestTimeout; PolishingService derives timeout from
defaultRequestTimeout+1 instead of hardcoding 15.
RED-8: ASRService.transcribe now emits .capability(onDeviceSupported:) as
first event per session; StatusBadge shows REC ⚠️ when the locale fell
back to cloud. New @Published var onDeviceSupported on State.

TEST-1: testPolishThrowsOnTransportTimeout now actually exercises
cancellation: StubURLProtocol delays response 5s, client.polish is
cancelled via Task.cancel(), test asserts the client throws .cancelled /
.transport / .decoding (was: silently passed).

TEST-2: New testPolisherSkipsNetworkWhenModeOff — PolishingService now
short-circuits when modeId == 'off' and returns trimmed input without
invoking LLMClient (proved via injected CountingLLMClient). Service was
moved to OSGKeyboardShared to be reachable from the test target.

TEST-3: KeyboardState (formerly KeyboardViewController.State) extracted
into OSGKeyboardShared so tests can @testable-import it. 5 phase/mode
tests in new KeyboardStateTests. Typealias preserves the old name.

TEST-4: New OSGKeyboardExtTests target with 6 tests covering State
initial values, phase transitions, structured-error round-trip, mode
switching, and InputMode rawValue round-trip.

project.yml

@@ -151,6 +151,22 @@ targets:
       base:
         PRODUCT_BUNDLE_IDENTIFIER: com.osgkeyboard.ios.tests
 
+  # =========================================================
+  # 键盘扩展单元测试 (TEST-4)
+  # =========================================================
+  OSGKeyboardExtTests:
+    type: bundle.unit-test
+    platform: iOS
+    sources:
+      - path: OSGKeyboardExtTests
+    info:
+      path: OSGKeyboardExtTests/Info.plist
+    dependencies:
+      - target: OSGKeyboardShared
+    settings:
+      base:
+        PRODUCT_BUNDLE_IDENTIFIER: com.osgkeyboard.ios.ext.tests
+
 schemes:
   OSGKeyboard:
     build:
@@ -163,5 +179,6 @@ schemes:
       config: Debug
       targets:
         - OSGKeyboardTests
+        - OSGKeyboardExtTests
     archive:
       config: Release