chore(mise): 13 phantom tools, a no-op [alias] block, and no Elixir

[hyperpolymath]

Context

mise.toml printed roughly 25 warning lines on every shell entry in this repo, while
installing none of the tools it warned about. It is developer-ergonomics only — CI does not
consume it — but it made every command in this repo, human or bot, arrive buried in noise.

Three faults

1. Thirteen tool names that do not exist in the mise registry.
denojs, pip, cargo, go-task, gofmt, isort, git, gnu-sed, gnu-grep,
gnu-tar, vitest, pytest, jest. Every one failed to resolve, so every one was pure
noise. Removed, grouped by reason in the file itself:

reason	names
already provided by a listed tool	cargo (rust), gofmt (go), pip (python)
project deps, not system tools	vitest, jest, pytest, isort
base system binaries	git, gnu-sed, gnu-grep, gnu-tar
simply misnamed	denojs → deno

go-task is dropped, not renamed. The bare name task does not work either:
mise registry lists it as aqua:go-task/task, but task@latest still fails to resolve.
That is a trap worth recording — appearing in mise registry output is not sufficient to
conclude a name resolves. I initially "verified" all names against registry listing and it
passed task; only running mise caught it.

2. erlang and elixir were absent entirely — despite Elixir being the language of
lib/ and all 71 test files. Now pinned to erlang 27.0 / elixir 1.17, matching what
tests.yml passes to erlef/setup-beam, so local mix test and CI run the same toolchain.

3. The [alias] block never did anything.

[alias]
build = "cargo build --release || npm run build || go build"
test  = "cargo test || npm test || go test ./..."

mise's [alias] maps an alias to a tool plugin — it does not define tasks, so none of
these ever ran (mise also warns it is deprecated in favour of [tool_alias]). Deliberately
not re-added as [tasks]: the Justfile already defines build, test, fmt,
fmt-check, lint, doctor and heal properly for the languages this repo actually uses.
Two task runners sharing verb names — one of which silently falls through || chains into a
different language's build — is worse than one.

Verification

Controlled comparison, one machine, one shell, both files read (the fixed copy in a
worktree, the unfixed copy in the parent checkout):

warnings citing the FIXED   file : 0
warnings citing the UNFIXED file : 14

Every retained name re-checked with mise ls-remote — resolution, not registry listing.

Expected remaining output

mise WARN  missing: erlang@27.0 elixir@1.17

until someone runs mise install. That warning is correct and actionable — it reports a
genuine local/CI toolchain gap, unlike the previous unfixable typos.

Acceptance criteria

• mise.toml parses as valid TOML
• Zero mise warnings attributable to this file
• Every tool name resolves via mise ls-remote
• No [alias] section
• Reviewer confirms dropping go-task is acceptable (nothing in-repo invokes task)

Model tier

Haiku/Sonnet — a single config file, no code paths, fully mechanical once the registry
facts are established. Recorded here so the pattern can be reused: several other estate
repos carry the same copied mise.toml.

Related

• fix(ci): arangodb probe can never pass (401) + stress-test fake/impossible steps #640 — CI fixes in tests.yml (separate concern, separate branch)