[camera] Add support for zero-shutter-lag capture - #12374

Android implementation of the zero-shutter-lag API added in
camera_platform_interface 2.14.0 (this bumps the constraint to
^2.14.0). Part of flutter/flutter#190598.
Measured on a Galaxy S21 (SM-G991N): the captured frame lands 629 ms
closer to the shutter tap, and shutter-to-file time drops 912 ms ->
639 ms (methodology and raw numbers in the issue).

- `isZeroShutterLagSupported` ->
  [`CameraInfo.isZslSupported()`](https://developer.android.com/reference/androidx/camera/core/CameraInfo#isZslSupported())
- `setZeroShutterLagEnabled` ->
  [`ImageCapture.Builder.setCaptureMode`](https://developer.android.com/reference/androidx/camera/core/ImageCapture.Builder#setCaptureMode(int))
  with
  [`CAPTURE_MODE_ZERO_SHUTTER_LAG`](https://developer.android.com/reference/androidx/camera/core/ImageCapture#CAPTURE_MODE_ZERO_SHUTTER_LAG)

CameraX degrades on its own, and only for still capture. Per the
CAPTURE_MODE_ZERO_SHUTTER_LAG reference above, the mode is disabled
automatically when VideoCapture is bound, flash mode is not OFF, or an
OEM extension is active. The granularity differs: flash falls back per
shot
([`CaptureConfigAdapter.kt`](https://github.com/androidx/androidx/blob/androidx-main/camera/camera-camera2/src/main/java/androidx/camera/camera2/adapter/CaptureConfigAdapter.kt#L133-L138)),
while a device without private reprocessing never activates the ZSL
session at all
([`ZslControl.kt`](https://github.com/androidx/androidx/blob/androidx-main/camera/camera-camera2/src/main/java/androidx/camera/camera2/adapter/ZslControl.kt#L138-L150)).
Apps need no special handling.

<details><summary>Why the ImageCapture use case is recreated</summary>

CameraX only accepts the capture mode at `Builder` time, so
`setZeroShutterLagEnabled` unbinds and recreates the `ImageCapture` use
case — the same approach the existing `setJpegImageQuality` uses for
the same constraint. Both are refactored onto one shared
`_recreateImageCapture()` helper, so both settings (`jpegQuality`, ZSL)
are always reapplied together; `createCamera` applies them on initial
construction as well. Regression tests cover both directions.

</details>

<details><summary>Experimental-API opt-in</summary>

Both CameraX members are annotated
[`@ExperimentalZeroShutterLag`](https://developer.android.com/reference/androidx/camera/core/ExperimentalZeroShutterLag),
a `@RequiresOptIn` marker consumed per declaration. Handled with
`@OptIn`, matching this plugin's existing opt-ins
(`ExperimentalCamera2Interop`, `ExperimentalLensFacing`,
`ExperimentalPersistentRecording`); no build configuration change and
nothing reaches the Dart surface. Verified clean against the repo's
lint setup (`warningsAsErrors` + baseline) with `gradlew lintDebug`.

</details>

iOS implementation of the zero-shutter-lag API added in
camera_platform_interface 2.14.0 (this bumps the constraint to
^2.14.0). Part of flutter/flutter#190598.

## What

- `isZeroShutterLagSupported` ->
  [`AVCapturePhotoOutput.isZeroShutterLagSupported`](https://developer.apple.com/documentation/avfoundation/avcapturephotooutput/iszeroshutterlagsupported)
  (iOS 17+/macOS 14+; `false` on older versions)
- `setZeroShutterLagEnabled` ->
  [`AVCapturePhotoOutput.isZeroShutterLagEnabled`](https://developer.apple.com/documentation/avfoundation/avcapturephotooutput/iszeroshutterlagenabled)

## Why explicit control when iOS auto-enables it

Per the `AVCapturePhotoOutput.h` header, "For apps linked on or after
iOS 17 zero shutter lag is automatically enabled when supported." The
documented role of the setter is the explicit opt-out (WWDC23 session
10105: "you can set AVCapturePhotoOutput.isZeroShutterLagEnabled to
false to opt out" - https://developer.apple.com/videos/play/wwdc2023/10105/),
plus deterministic re-enable: support can be revoked by configuration
changes, and when it is, the enabled state silently reverts.

Because of that auto-enable, iOS 17+ starts with zero shutter lag on
while Android starts with it off, so the same Dart call is an opt-out
here and an opt-in there. No latency numbers are quoted for iOS: the
platform already enables the mode by default, so this change is about
making that state explicit and controllable, not about improving it.

<details><summary>Guard and configuration timing</summary>

The header states the property "may only be set to YES if
zeroShutterLagSupported is YES, otherwise an NSInvalidArgumentException
is thrown", and that changing it "requires a lengthy reconfiguration of
the capture render pipeline", to be done within
`beginConfiguration`/`commitConfiguration` while running. The
implementation guards enabling on the support query and wraps the write
in a configuration block. The requested state is kept (plugin- and
camera-level) and reapplied after session reconfigurations and camera
switches, which silently reset it — mirroring the settings-retention
approach on the Android side. Availability is handled inside the
`CapturePhotoOutput` protocol passthrough (`flutter`-prefixed members,
matching the existing `CaptureDevice.flutterActiveFormat` pattern), so
callers need no availability checks and pre-iOS 17 devices report
unsupported / ignore writes.

</details>

Regenerating with pigeon 26.1.5 also reverts two pre-existing hand-edits
to the generated files from flutter#11616 (a redundant Int32 fallback cast and
a missing Dart doc comment).

Generated with the repo tool per the federated-plugin process
(https://github.com/flutter/flutter/blob/master/docs/ecosystem/contributing/README.md#changing-federated-plugins):

    dart run script/tool/bin/flutter_plugin_tools.dart \
        make-deps-path-based --target-dependencies=camera_platform_interface

CI is expected to be red on the publish check only; that check clears
when this commit is reverted after the platform interface change is
published. Part of flutter/flutter#190598.

…-lag

# Conflicts:
#	packages/camera/camera_android_camerax/CHANGELOG.md
#	packages/camera/camera_android_camerax/pubspec.yaml
#	packages/camera/camera_avfoundation/CHANGELOG.md
#	packages/camera/camera_avfoundation/darwin/camera_avfoundation/Sources/camera_avfoundation/Messages.swift

Upstream bumped pigeon to ^27.3.2 (camera_avfoundation 0.10.3,
camera_android_camerax 0.7.4+7). Re-run pigeon so the zero-shutter-lag
additions are generated with the same version; bump camera_avfoundation
to 0.10.4 (0.10.3 already taken upstream).

…-lag

# Conflicts:
#	packages/camera/camera/CHANGELOG.md
#	packages/camera/camera_android_camerax/CHANGELOG.md
#	packages/camera/camera_avfoundation/CHANGELOG.md
#	packages/camera/camera_platform_interface/CHANGELOG.md

…-lag