Improve GitHub-flavored Markdown rendering

{
  "backend": {
    "author": {
      "email": "drschwabe@fastmail.com",
      "name": "Derrick Schwabe",
      "time": 1788320662
    },
    "commit": "git:sha1:f9716594a73aa026dac422d0ed13976b76344c14",
    "committer": {
      "email": "drschwabe@fastmail.com",
      "name": "Derrick Schwabe",
      "time": 1788320662
    },
    "manifest": "mmm-manifest:sha256:9ac0df322843a21a08358022f6d7f87dfe9b657f85789596674af2d97fedab34",
    "message": "Improve GitHub-flavored Markdown rendering\n\nAdd a modular GFM renderer for common README variants and standalone Markdown files, with scoped GitHub-like typography for lists, task items, tables, blockquotes, and code. Restore visible list markers, update the Clone popout for authenticated push, and cover the rendering pipeline with focused tests.",
    "objectFormat": "sha1",
    "parents": [
      "git:sha1:12029eb2d9d151128001af3c3efc557dd753c49c"
    ],
    "ref": "refs/heads/master",
    "summary": "Improve GitHub-flavored Markdown rendering",
    "tree": "git:sha1:5aa80cdb9129c950e9f174ea35290f559ff11ebf",
    "type": "git"
  },
  "issuedAt": "2026-09-02T06:14:08.634Z",
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