chore(scripts): remove the broken installer

[LKSNDRTMLKV]

Removes scripts/install.sh rather than repairing it — a repaired script would still have nothing to install. The replacement, written against published and pinned artefacts, is #397 (target: before 1.0).

Why not repair it

Every source it installs from is unpublished, checked today:

The script	Reality
curl -sSL https://odal-node.io/install.sh	404 — the facade does not serve it
downloads https://odal-node.io/docker-compose.yml	404, and with no --fail it saves the 404 page as docker-compose.yml
pulls ghcr.io/odal-node/*:latest	the packages are private; an anonymous pull is refused
cargo install odal-cli when cargo exists	🚨 odal-cli is not on crates.io — whoever registers the name runs code on every machine following the installer
falls back to releases/download/latest/odal-<os>-<arch>	404 — no GitHub Release exists, and releases/download/latest/ is not a valid URL shape

And what it would have run, had the fetches worked:

• .env lacks DATABASE_APP_PASS, DATABASE_POSTGRES_PASS and the admin credentials, which compose requires via ${…:?} — docker compose up fails at interpolation. It writes PORT where compose maps NODE_PORT, so --port breaks the health poll, and it still writes the dead JWKS_URL/JWT_* variables.
• The compose file placed at the install root reads env_file: ../.env and bind-mounts ../ops/bootstrap/* — so from ~/.odal/ it reads ~/.env, and Docker creates empty directories for the missing mounts, so Postgres role provisioning silently never runs.
• It prints a locally generated odal_sk_… as "API Key". The node never issued it; it authenticates nothing.

What changes

• scripts/install.sh — deleted.
• scripts/README.md — was entirely about the installer (and described a scripts/docker-compose.yml and an installer/ directory that do not exist); now says what scripts/ holds and points installers at OPERATOR-SETUP.md and Rebuild the one-click installer once the images and CLI are public (pre-beta) #397.
• justfile — the comment claiming "the installer path was never affected" was false (see above); it now names odal up, which does pass --env-file itself.
• .gitattributes, CONTRIBUTING.md — stop naming the script.
• OPERATOR-SETUP.md — "or download a release" removed; there is none.
• CHANGELOG.md — ### Removed under [0.14.0], since this lands before the tag.

No behaviour change: nothing in the workspace, CI or the images referenced the script.

Merge order

After #394. That PR adds one line to install.sh; this deletes the file, so rebasing onto main after it merges is a modify/delete conflict resolved by keeping the deletion.

Verified

just check green on this branch. No install.sh reference remains outside the changelog entry.