fix(ci): align the Idris2 version assert with the pinned image (0.8.0) (#31)

Now that #30 made the assert diagnosable, the real mismatch is visible:

```
idris2 --version -> Idris 2, version 0.8.0-6ca00e72e
::error::expected Idris 2 0.7.0
```

The digest-pinned `idris2-pack` image ships **0.8.0**, so the `0.7.0`
assertion
could never have matched — `CI / required` has never passed on its own
terms.
This is the last red check on `main`.

## Which side is wrong?

Nothing in the repository actually requires 0.7.0:

- `abi.ipkg` declares **no version constraint** — it depends only on
`base`.
- The `idris2 0.7.0` line in `.tool-versions` is **commented out**, so
it pins nothing.
- The only 0.7.0 references were the workflow asserts and their
comments.

So "0.7.0" was stale documentation that drifted from the digest. The
**immutable
digest is the authority**, and the version notes are brought into step
with it
rather than the reverse. The typecheck now actually runs against the
toolchain
that is genuinely installed.

Also fixes the identical brittle assert in **`release.yml`**, which
piped
`idris2 --version` into `grep -Fx` under `pipefail` exactly as `ci.yml`
did — it
would have failed the same way, silently, on the next release.

## If 0.7.0 was intended

Then the fix is the other direction: re-pin the container to a 0.7.0
image digest.
Say so and I will swap it — but the current pair is contradictory either
way.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>

Author: hyperpolymath

.github/workflows/ci.yml

@@ -20,7 +20,8 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 20
     container:
-      # Idris 2 0.7.0, pinned by immutable image digest.
+      # Idris 2 0.8.0, pinned by immutable image digest.
+      # The digest is the authority; keep the version note in step with it.
       image: ghcr.io/stefan-hoeck/idris2-pack@sha256:de9781906050dc44704ec6de0108c86f899ef17b2642932b79e00245d613b8ad
     steps:
       - name: Checkout
@@ -54,8 +55,8 @@ jobs:
           ver="$(idris2 --version)"
           echo "idris2 --version -> ${ver}"
           case "$ver" in
-            *"0.7.0"*) ;;
-            *) echo "::error::expected Idris 2 0.7.0, got: ${ver}"; exit 1 ;;
+            *"0.8.0"*) ;;
+            *) echo "::error::expected Idris 2 0.8.0, got: ${ver}"; exit 1 ;;
           esac
           idris2 --typecheck abi.ipkg
 

.github/workflows/release.yml

@@ -34,7 +34,13 @@ jobs:
         shell: bash
         run: |
           set -euo pipefail
-          idris2 --version | grep -Fx 'Idris 2, version 0.7.0'
+          # Same fix as ci.yml: never assert through a pipe under pipefail.
+          ver="$(idris2 --version)"
+          echo "idris2 --version -> ${ver}"
+          case "$ver" in
+            *"0.8.0"*) ;;
+            *) echo "::error::expected Idris 2 0.8.0, got: ${ver}"; exit 1 ;;
+          esac
           idris2 --typecheck abi.ipkg
           (
             cd src/interface/ffi

.tool-versions

@@ -6,5 +6,5 @@
 # elixir 1.18.0
 # erlang 27.2
 # zig 0.14.0
-# idris2 0.7.0
+# idris2 0.8.0
 rust nightly