Keep picks in the page address and add a copyable release post

[lesnik512]

What

• The site keeps the picked tags in the address after #, as team/api=2.4.0&team/web=5.12.0. A reload or a shared link restores them. Editing the hash in an open tab applies it too.
• Release gets a Release post box with a copy button. It holds one Markdown text: a line per picked tag with its compare link and pipeline, then the deduplicated Jira tasks with summaries.

Decisions

• When the hash is present, it holds the whole selection. A service it does not name has no pick, even if the report has a release tag for it, so a shared link shows the same picks to everyone who opens it.
• Picks that are no longer in the report, such as a tag dropped by a later scheduled run or an unknown service, are skipped. A warning names them.
• history.replaceState writes the hash, so picking adds no history entries and fires no hashchange.
• Clearing every pick empties the hash. A plain # can't be told apart from no hash, so on reload the page falls back to the release tags. I accepted this edge case rather than add a sentinel value.
• / stays readable in the hash; everything else in project paths and tag names is percent-encoded.
• The post reuses the data behind the existing lists. Summaries are not Markdown-escaped, same as the task list.

Checks

• just lint and just test-ci pass: 109 tests, 100% coverage. The page has no automated tests.
• Checked by hand in a browser against sample and --jira reports:
  • a link with a valid pick, a stale tag, and an unknown service;
  • clicking pick updates the hash and closes the line;
  • hashchange in an open tab;
  • the /index.html path;
  • clearing every pick;
  • the --jira default pick written into the hash;
  • the release post output.