Feature: JSS as a CORS proxy for git remotes (with optional paid access via HTTP 402) #377

Background

JSS already exposes git smart-HTTP via --git and supports HTTP 402 paid access via --pay. Combining these would let a JSS pod act as a CORS-enabled, optionally-paid gateway for browser-side git clients to any remote git server (GitHub, GitLab, Gitea, other JSS pods, etc.).

Why

Browser-side git clients (e.g., JSS Git, built on isomorphic-git) hit CORS preflight failures against major git hosts that don't return browser-friendly headers. Public CORS proxies (cors.isomorphic-git.org) exist but introduce third-party dependencies, privacy concerns, and uptime risk.

A JSS-native proxy would let pod operators:

• Self-host the bridge (no third-party trust)
• Optionally monetize the proxy via per-request HTTP 402 pricing
• Stay within the Solid + Lightning stack already shipping in JSS

Proposed feature

New flag --git-proxy enables a proxy endpoint that:

1. Accepts requests at /git-proxy/<remote-url-or-path>/info/refs?...
2. Forwards the request to the remote git host with appropriate headers (Git-Protocol, Authorization if provided)
3. Returns the response with CORS headers attached (Access-Control-Allow-Origin, Access-Control-Allow-Headers: Git-Protocol, Content-Type, etc.)
4. Handles binary responses (pack files) correctly
5. Optionally pricing-gated via HTTP 402 (--pay integration: each proxy request debits the caller's balance per --pay-cost)

URL scheme options

Recommend B for cleaner URLs and easier client handling.

Composing with --pay

Pricing tiers (configurable):

• Free up to N requests/hour per WebID (rate-limited)
• Paid above that: deduct --pay-cost per request from caller's ledger balance
• HTTP 402 returned when balance insufficient
• Bandwidth-priced option (--pay-per-byte) for large clones

Marketing story

"JSS Git browses any git repo — your pod, GitHub, Gitea, anywhere — by routing through a pod-hosted proxy. Free for friends; sat-per-request for strangers."

Pulls together: Solid + git smart-HTTP + Lightning + browser-side cloning. A complete decentralized git-hosting story.

Refs

• src/handlers/git.js — existing git handler
• src/handlers/pay.js — existing payment + ledger
• src/wac/checker.js — WAC payment conditions
• JSS Git frontend: github.com/JavaScriptSolidServer/git
• isomorphic-git CORS proxy spec: https://isomorphic-git.org/docs/en/cors