## Description
Adds PEER_URL env variable for setting peer URL (query param still takes
priority if set).
- Useful for self-hosters
- Was a pain to figure out
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
- New Features
- Support configuring the peer server URL via an environment variable,
with automatic fallback to the URL parameter or a default.
- Server-provided configuration is securely passed to the client to
simplify deployment setup.
- Chores
- Excluded common build artifacts and IDE directories from container
contexts to reduce image size and speed up builds.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Co-authored-by: DatCaptainHorse <DatCaptainHorse@users.noreply.github.com>
