[vector_graphics_compiler] Add example for pub.dev Example tab

[sheershtehri7]

Creates a standalone example app in vector_graphics_compiler/example/ demonstrating the build-time SVG asset transformer with AssetBytesLoader. Adds example/example.md for the pub.dev Example tab and updates the package README with a link to the new example.

Fixes flutter/flutter#183947

Pre-Review Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the AI contribution guidelines and understand my responsibilities, or I am not using AI tools.
• I read the Tree Hygiene page, which explains my responsibilities.
• I read and followed the relevant style guides and ran the auto-formatter.
• I signed the CLA.
• The title of the PR starts with the name of the package surrounded by square brackets, e.g. [shared_preferences]
• I linked to at least one issue that this PR fixes in the description above.
• I followed the version and CHANGELOG instructions, using semantic versioning and the repository CHANGELOG style.
• I updated/added relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or I have commented below to indicate which test exemption this PR falls under¹.
• All existing and new tests are passing.

Footnotes

1. Regular contributors who have demonstrated familiarity with the repository guidelines only need to comment if the PR is not auto-exempted by repo tooling. ↩

[flutter-dashboard]

It looks like this pull request may not have tests. Please make sure to add tests or get an explicit test exemption before merging.

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[gemini-code-assist]

Code Review

This pull request adds an example for the vector_graphics_compiler package. It introduces an example.md file and updates the main README.md to point to a new, more comprehensive example. The example application in the vector_graphics package is extended to demonstrate both runtime SVG loading via NetworkSvgLoader and build-time SVG compilation using an asset transformer with AssetBytesLoader. A new SVG asset is added for this purpose, and the pubspec.yaml is updated accordingly. The review includes a suggestion to replace hardcoded spacing values with constants to improve maintainability.

[sheershtehri7]

This PR adds only documentation (example/example.md, README.md update) and example app code (extending the existing vector_graphics example). No production library logic is changed, so no new tests are needed and no version bump or CHANGELOG update is required. The CHANGELOG checklist item is intentionally left unchecked for this reason.

[stuartmorgan-g]

Thanks for the contribution!

No production library logic is changed, so no new tests are needed and no version bump or CHANGELOG update is required. The CHANGELOG checklist item is intentionally left unchecked for this reason.

The CHANGELOG checklist item has two options; doing one of them is required, which is why it's on the checklist. If you believe that this PR falls under the documented exceptions, then you should list the specific documented exception(s) that this falls under and check the item.

[stuartmorgan-g]

Is there a reason we can't add a widget test to the example that verifies that this widget is loaded and has the correct size, so that we have an automated test that the example is doing what we expect?

[sheershtehri7]

the restructured standalone example app includes test/widget_test.dart which verifies:
The app bar title 'Build-time SVG Transformer' is present
The SizedBox wrapping the VectorGraphic has the correct 200×200 dimensions
Happy to extend the test coverage further if needed.

[sheershtehri7]

Thanks for the contribution!

No production library logic is changed, so no new tests are needed and no version bump or CHANGELOG update is required. The CHANGELOG checklist item is intentionally left unchecked for this reason.

The CHANGELOG checklist item has two options; doing one of them is required, which is why it's on the checklist. If you believe that this PR falls under the documented exceptions, then you should list the specific documented exception(s) that this falls under and check the item.

This PR falls under the documented exception for "PRs that only affect unpublished parts of example apps" from the Version and CHANGELOG section of the contributing guide.
The only change to the published package is the README.md update. However, I acknowledge the guide also notes:
Even version exempt changes should often include a CHANGELOG entry, since some changes (e.g., certain updates to examples) that do not need to be published may still be of interest to clients.
Given that the README.md now links to a new example app, I'm happy to add a NEXT CHANGELOG entry to vector_graphics_compiler if you'd like — something like:
NEXT - Adds example app demonstrating build-time SVG asset transformation.

Please let me know your preference and I'll update accordingly.

[stuartmorgan-g]

This PR falls under the documented exception for "PRs that only affect unpublished parts of example apps"

example/lib/main.dart is published on pub.dev, so is not an unpublished part of the example app.

The only change to the published package is the README.md update.

The package README isn't part of the example app at all, so cannot fall under an exemption that only applies to the example app.

Please see also https://github.com/flutter/flutter/blob/master/docs/ecosystem/contributing/README.md#faq

[sheershtehri7]

This PR falls under the documented exception for "PRs that only affect unpublished parts of example apps"

example/lib/main.dart is published on pub.dev, so is not an unpublished part of the example app.

The only change to the published package is the README.md update.

The package README isn't part of the example app at all, so cannot fall under an exemption that only applies to the example app.

Please see also https://github.com/flutter/flutter/blob/master/docs/ecosystem/contributing/README.md#faq

You're right on both counts, I apologize for the incorrect exception claim. I've added a patch version bump (1.2.0 → 1.2.1) and CHANGELOG entry covering the README update and example app addition.