refactor: use curl ghcr image, install starshp from gh release

[kemingy]

• use curl ghcr image, this can avoid docker hub auth timeout and extremely long latency, part of the feat: adopt ghcr #1959
• install starship from the curl
• update starship config
• rm starship from base image and release

[Copilot]

Pull Request Overview

This PR migrates starship installation from a Docker image approach to downloading directly from GitHub releases, and updates the base curl image used across various language installers. The primary goals are to simplify the build process and update dependencies.

• Removes the custom envd-starship Docker image and Dockerfile
• Updates the curl base image from curlimages/curl:8.11.1 to ghcr.io/curl/curl-container/curl-multi:8.17.0
• Implements direct download of starship binary from GitHub releases
• Adds additional language symbols to the starship configuration

Reviewed Changes

Copilot reviewed 14 out of 14 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
pkg/types/envd.go	Removes unused EnvdStarshipImage constant
pkg/lang/ir/v1/starship.go	New file implementing starship download from GitHub releases
pkg/lang/ir/v1/system.go	Removes old compileStarship function that used Docker image
pkg/lang/ir/v1/shell.go	Adds language-specific symbols for pixi, conda, nodejs, go, rust, julia, and rlang to starship config; updates fish shell download to use new curl image
pkg/lang/ir/v1/conda.go	Renames builderImage to curlImage and updates to new curl container version
pkg/lang/ir/v1/uv.go	Updates to use renamed curlImage constant
pkg/lang/ir/v1/rust.go	Updates to use renamed curlImage constant
pkg/lang/ir/v1/pixi.go	Updates to use renamed curlImage constant
pkg/lang/ir/v1/nodejs.go	Updates to use renamed curlImage constant
pkg/lang/ir/v1/julia.go	Updates to use renamed curlImage constant
pkg/lang/ir/v1/golang.go	Updates to use renamed curlImage constant
pkg/lang/ir/v1/agent.go	Updates to use renamed curlImage constant
base-images/envd-starship/envd-starship.Dockerfile	Removes the entire Dockerfile as it's no longer needed
.github/workflows/release.yml	Removes the workflow job for building and publishing the starship Docker image

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.