Rename app.py to main.py in template

[eerhardt]

This makes the template apphost.cs a little easier to read. It also follows some standard conventions for file naming.

[github-actions]

🚀 Dogfood this PR with:

⚠️ WARNING: Do not do this without first carefully reviewing the code of this PR to satisfy yourself it is safe.

curl -fsSL https://raw.githubusercontent.com/dotnet/aspire/main/eng/scripts/get-aspire-cli-pr.sh | bash -s -- 12628

Or

• Run remotely in PowerShell:

iex "& { $(irm https://raw.githubusercontent.com/dotnet/aspire/main/eng/scripts/get-aspire-cli-pr.ps1) } 12628"

[Copilot]

Pull Request Overview

This PR refactors the Python starter template to align the application structure with standard FastAPI conventions. The main change renames the Python application module from app.py to main.py and updates the Uvicorn app reference accordingly.

Key changes:

• Updated the Uvicorn ASGI import path from "app:app" to "main:app" in apphost.cs
• Added a new main.py file containing the complete FastAPI application with weather forecast API, health check endpoint, Redis caching support (conditional), OpenTelemetry instrumentation, and static file serving

Reviewed Changes

Copilot reviewed 1 out of 2 changed files in this pull request and generated no comments.

File	Description
apphost.cs	Updated the AddUvicornApp call to reference "main:app" instead of "app:app" to match the new module naming
app/main.py	New FastAPI application module with complete implementation including weather forecast API, optional Redis caching, health checks, and telemetry integration

[davidfowl]

/backport to release/13.0

[github-actions]

Started backporting to release/13.0: https://github.com/dotnet/aspire/actions/runs/19044636479