Add support for Python 3.14

[jonathan343]

Note

This PR builds on top of #2162 and should be merged subsequently. After merging, this PR will rebased and will result in a smaller reviewable diff.

Addresses #2150 , #2153, and #2167

Summary

This PR adds support for Python 3.14 by updating compatibility checks, runtime mappings, development dependencies, the v2 pipeline CodeBuild image, and tests.

It also includes a packager change so chalice can fetch wheels built for newer manylinux profiles. Pip treats --platform as a literal tag and won't extrapolate to lower manylinux_X_Y versions, so chalice now emits when downloading manylinux wheels. Without this, Python 3.14 wheels of pandas/numpy/scipy (which only ship as manylinux_2_24+) can't be packaged.

Testing

I deployed a modified version of the sample Lambda handler that prints the python version. The steps to reproduce are provided below:

1. Create and activate a Python 3.14 virtual environment

$ uv venv -p 3.14
$ source .venv/bin/activate

2. Install Chalice

$ uv pip install -e .

3. Create a test application and cd into the project dir

$ chalice new-project helloworld
$ cd helloworld

5. Modify the generated app.py file to print the python version:

import platform
from chalice import Chalice

app = Chalice(app_name='helloworld')


@app.route('/')
def index():
    return {
        'hello': 'world',
        'python_version': platform.python_version()
    }

6. Deploy the test app

$ chalice deploy

7. Validate the test app was deployed successfully

$ curl <rest_api_url>
{"hello":"world","python_version":"3.14.3"}

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.