docs: refresh official jsbgl package metadata

[Luzijano]

Summary

• updates package repository/bugs/homepage metadata from the original upstream fork to BitgesellOfficial/jsbgl
• refreshes README status/package links from stale jsbtc/jsbtc.js references to jsbgl
• updates README test link to the current official repo/default branch path

Validation

• RED/proof before fix: local metadata assertion failed while stale bitaps-com/jsbgl, jsbtc, and jsbtc.js references were present
• GREEN/proof after fix: metadata assertion passes
• node -e "JSON.parse(require('fs').readFileSync('package.json','utf8')); console.log('package json parses')"
• git diff --check

Submitted under the Bitgesell bounty/improvement program (BitgesellOfficial/bitgesell#81). No payout address posted unless/until accepted or requested.

AI/tooling disclosure: prepared with Hermes Agent automation.