docs(web): add the v0.11.0 release blog post (#171)

## Linked issue

Fixes #170

## Summary

Adds `web/src/content/blog/what-shipped-in-v0-11-0.md`, the release post
for v0.11.0.

The angle is that v0.11.0 was mostly written by other people, so the
post is organised around that rather than around a changelog dump:

- **Four new command groups**, each credited to its author with the PR
linked: `emoji` and `team` and `usergroups` (@tmack8001), `files`
(@lelouvincx).
- **Two changes with no visible surface**: the process-wide rate limiter
(#151) and why tripping `unexpected_api_call_volume` signs a browser
session out on Enterprise Grid, plus the wider `--json` coverage and
`--message-file` (@ajayraho, @rafael-yure). Also singles out #155, a bug
that broke nothing for users and blocked every Windows contributor.
- **Why the constitution earns its cost**: the write commands arrived
with the confirmation gate already correct and the file commands
accepted Slack URLs unasked, because both rules were written down before
the code was.

No em dashes, matching the tone of the two existing posts. `featured` is
left on `slack-without-a-slack-app`; the index already labels the newest
post "Latest".

Docs-only, no CLI change, so no CHANGELOG entry — the changelog tracks
the binary's behaviour, and site content has not been listed there
before.

## Checklist

- [x] The linked issue is open and carries the `ready-for-pr` label
(constitution §1–2)
- [x] Change is focused on the linked issue — no unrelated edits
- [x] Tests added/updated, including edge cases (constitution §4) — n/a,
single content file with no code paths; covered by the site build and
link check below
- [x] `bun run type-check` and `bun test` pass locally — plus `npm run
build` and `npm run check:links` in `web/`: 32 pages, every internal
link and fragment resolves (the four `/docs/user-guide/` links in the
post are verified by it)
- [x] Pre-commit hooks are installed and passing — no `--no-verify`, no
`SKIP=`
- [x] All commits are signed (constitution §5)
- [x] Documentation in `docs/` updated, added, or deleted as needed
(constitution §7)
- [x] No tokens, credentials, or user data handled insecurely

Co-authored-by: Shaharia Azam <mail@shaharia.com>