The AI contribution guidelines were moved to a separate page; this updates the checklist to link to the new location.

…rt the package (#13447)

Since 2.6.0 (#12329), `package:shared_preferences_foundation/shared_preferences_foundation.dart` transitively imports `dart:ffi` and `package:objective_c`, causing multi-platform apps that import it (for example to use `SharedPreferencesAsyncFoundationOptions`) to fail compilation on web. This currently breaks `shared_preferences/example` web drive tests in CI.

Following the same approach as `shared_preferences_android` in #13380, this conditionally exports a stub of the plugin classes when `dart.library.ffi` is unavailable and moves `SharedPreferencesAsyncFoundationOptions` into its own FFI-free file.

Updates out-of-date documentation for typography, which is missing reference to the 2021 theme (the current default).

Fixes flutter/flutter#195013

## Pre-Review Checklist

**Text exemption:** Documentation changes only.

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…defaults (#13374)

`TextTheme.debugFillProperties` and `Typography.debugFillProperties` decide which values to report by comparing them against a default. Both defaults were out of date:
- `TextTheme` compared against `Typography.material2018(...).black`
- `Typography` compared against `Typography.material2014()`

This PR:
- compares `TextTheme` styles against `ThemeData.fallback().textTheme`.
- compares `Typography` text themes against `ThemeData.fallback().typography`. This matches how `ThemeData.debugFillProperties` already reports typography.
- Treats null `TextTheme` styles as default. When a `TextTheme` is merged into a `ThemeData`, a null style falls back to the default style, so it shouldn't be reported as a difference.

Fixes flutter/flutter#194981

## Pre-Review Checklist

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…v_bar_transition_test, refresh_test, route_test, text_field_cursor_test (#13439)

Removes the whole-file `@TestOn('!chrome')` annotations from four `cupertino_ui` test files so they run on the web:

- `nav_bar_transition_test.dart`
- `refresh_test.dart`
- `route_test.dart` (keeps the existing targeted web skip on the state restoration test)
- `text_field_cursor_test.dart`

All of the newly enabled tests pass on Chrome under both CI web renderers: CanvasKit (`flutter test --platform chrome`) and Skwasm (`flutter test --platform chrome --wasm`). None of them use golden files. Leaving the skips in place hides web regressions in these widgets.

Part of flutter/flutter#33615 (the original web limitation behind these skips is closed; the one test that still depends on state restoration stays skipped on web).

This is a test-only change, so it is exempt from version and CHANGELOG updates.

## Pre-Review Checklist

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…13287)

SVG allows `x`, `y`, `dx` and `dy` on `text` and `tspan` to be a list, one value per character. The compiler parsed them as a single number, so a list like `x="0 4.86 10.01"` threw a confusing `FormatException: Invalid double`.

Lists aren't supported, so it now throws an `UnimplementedError` that names the attribute and value. Single values work as before.

Fixes flutter/flutter#165490

## Pre-Review Checklist

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This PR ports my changes from flutter/flutter#188258 to
  flutter/packages,
  as part of flutter/flutter#188444          

  Adds `Checkbox.markInsets` and `CheckboxThemeData.markInsets`, which inset the check
  mark and the
  indeterminate dash within the checkbox without changing the size of the box itself. The
  mark and its
  stroke shrink proportionally, and the mark is not painted if the insets leave no room.

  Fixes flutter/flutter#188031                      

  ## Tests

  Added to `packages/material_ui/test/checkbox_test.dart`:
  - `Checkbox.markInsets` defaults to null
  -  Checkbox with no `markInsets` paints the check at full stroke width (backward-compat)
  - `Checkbox.markInsets` shrinks the check mark and its stroke
  - `Checkbox.markInsets` shrinks the indeterminate dash
  - `Checkbox.markInsets` larger than the box collapses the mark without crashing
  - `Checkbox.markInsets` falls back to `CheckboxThemeData.markInsets`
  - `Checkbox.markInsets` overrides `CheckboxThemeData.markInsets`

  ## Pre-Review Checklist

  submitting PRs.
  am not using AI tools.
  brackets, e.g. `[shared_preferences]`
  and the [repository CHANGELOG style], or I have commented below to indicate which
  documented exception this PR falls under[^1].
  indicate which [test exemption] this PR falls under[^1].
  
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…13370)

Delegate unlocalized trigger fallback in `_LocalizedShortcutLabeler.getShortcutLabel` directly to `trigger.keyLabel` instead of masking `keyId` with `LogicalKeyboardKey.planeMask` (`0x0ff00000000`), which truncates to `0` under 32-bit JS bitwise `&` and renders keys like `Tab` and `F1` as raw char codes (`\t`, `\u0801`).

Fixes flutter/flutter#195003

## Pre-Review Checklist

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…eferencesPlugin` until first use on Android (#13431)

Defers `getSharedPreferences` in `LegacySharedPreferencesPlugin` out of `onAttachedToEngine` until first use, avoiding synchronous disk I/O on the Android main thread during startup.

The following screenshot shows that the time taken for `RegisterFlutterPlugin` significantly decreases with the change, which validates the fix:
<img width="1920" height="552" alt="shared_preferences_registration_comparison_perfetto" src="https://github.com/user-attachments/assets/c1fea032-a499-4fa4-91de-13648ea03999" />

I also previously implemented this in my app, which was later negated by an upgrade of the shared_preferences packages into g3 and caused cold startup latency regression alerts on my app. Hoping to upstream the fix to get this optimization to all Flutter users.

flutter/flutter#195313 will be fixed by this PR.

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…erial2021` (#13443)

Adds a deprecation message to the black/white parameters in the `Typography.material2021` factory constructor.

Fixes flutter/flutter#195200

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