hx: download ældre versioner

What's Changed
- docs: align README and metadata with the new arcanist.sh/hx by @raffaelschneider in #68
- Locked builds: hx build/test/run use hx.lock; --locked; flake.lock workflow by @raffaelschneider in #69
- chore(nix): update flake.lock by @github-actions[bot] in #70
- ci: submit releases to winget by @raffaelschneider in #71
- release: v0.11.0 by @raffaelschneider in #72
New Contributors
- @github-actions[bot] made their first contribution in #70
Full Changelog: v0.10.1...v0.11.0

> **If you use the Helix editor, or installed hx via Homebrew:** this release
> may install hx under the name **`hxs`** instead of `hx`. Helix's binary is also
> called `hx`, and hx now steps aside rather than colliding. Every command works
> the same, spelled `hxs`. The installer tells you when it does this; Homebrew
> does it unconditionally, so `brew upgrade` replaces an existing `hx` with `hxs`.
> Run `hx doctor` (or `hxs doctor`) to see which names are in play on your
> machine, and see the Changed section below for how to keep the short name.

### Changed
• **The binary name is no longer fixed to `hx`.** The Helix editor's binary is
also called `hx` and ships in most distributions, so a machine can end up with
two executables under one name — whichever comes first on `PATH` wins and the
other becomes unreachable. hx now adapts instead of colliding.
• The CLI derives its command name from `argv[0]`, so help text, usage,
parse errors, completions and man pages all follow the name the binary was
actually installed under. Previously these were hardcoded：a renamed binary
printed `hx` throughout its help and, worse, generated shell completions
registered against `hx` — a command absent from that machine.
([#19](https://github.com/arcanist-sh/hx/pull/19))
• `install.sh` probes `PATH` and installs as **`hxs`** when something else
already owns `hx`, reporting it plainly. It distinguishes an upgrade from a
collision：an hx installed elsewhere keeps the name rather than being
silently renamed. `HX_BINARY_NAME` or `--binary-name` overrides in either
direction. ([#22](https://github.com/arcanist-sh/hx/pull/22))
• **Breaking for Homebrew tap users.** The generated formula now installs the
binary as `hxs`, so `brew upgrade` replaces an existing `hx` with `hxs`.
Homebrew removed formula options, so a formula cannot detect and adapt the
way `install.sh` does — one name has to serve every brew user. Renaming was
chosen over `conflicts_with "helix"` because a Haskell toolchain is not an
alternative to an editor and someone may reasonably want both. The formula's
caveats explain how to symlink the short name back.
([#25](https://github.com/arcanist-sh/hx/pull/25))
• ([#17](https://github.com/arcanist-sh/hx/issues/17))

### Added
• **`hx doctor` reports binary name collisions.** It warns in both directions —
when another `hx` shadows this one, and when this one shadows another, since
installing hx ahead of Helix silently breaks that editor. This covers the case
install-time detection cannot：installing hx first and Helix second. Stays
quiet when hx was not reached through `PATH` at all.
([#21](https://github.com/arcanist-sh/hx/pull/21))

### Fixed
• **Documented cache and config directory paths were wrong on macOS and
Windows.** `ProjectDirs` does not place the project at the top of the platform
directory：macOS joins the parts into a bundle id and Windows joins
organization and application. The real locations are
`~/Library/Caches/io.raskell.hx` and `%LOCALAPPDATA%\raskell\hx\cache`, not
`~/Library/Caches/hx` and `%LOCALAPPDATA%\hx\cache`. `cabal_store_dir()` was
also documented as `~/.hx/store` throughout but returns
`<global cache>/cabal/store`. These are the paths users follow to find or
clear their own cache, and on those platforms they did not exist.
([#23](https://github.com/arcanist-sh/hx/pull/23))
• **`hx upgrade` and `install.sh` targeted the pre-rename GitHub org.** Both
resolved `raskell-io/hx` and worked only by following a redirect; they now
name `arcanist-sh/hx` directly. The generated Homebrew formula and install
script did too, which meant regenerating the published tap formula would have
silently reverted a hand-applied fix. Project templates also wrote a
`raskell-io` link into every generated `hx.toml`.
([#26](https://github.com/arcanist-sh/hx/pull/26),
[#27](https://github.com/arcanist-sh/hx/pull/27))
• **The generated Homebrew formula could not install.** It referenced
`completions/*` files that the release archive does not