fix(codeql): analyse the languages this repository actually has (#41)

`codeql database finalize` was exiting **32** on every run:

> CodeQL could not process any code written in JavaScript/TypeScript.

The matrix asserted `javascript-typescript`; this repository's languages
are `rust`. One `codeql.yml` was copied estate-wide with a hard-coded JS
matrix — **82 repositories** carry it, and 17 of the 18 sampled have no
JavaScript at all (Julia, Rust, Zig, Agda, Ada, Haskell, Elixir).

**This is not only a failing check.** The crash uploads no SARIF, so a
`code_scanning` ruleset rule requiring CodeQL waits forever on *"Code
scanning is waiting for results from CodeQL"*. One fault, two symptoms —
and relaxing the rule's thresholds could not have helped, because no
results arrive at all.

`actions` is kept (or added): it is valid in every repository, since
every repository has workflow files, and it keeps this workflow
producing a check and a SARIF upload even where CodeQL can analyse
nothing else.

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

Signed-off-by: Jonathan D.A. Jewell <6759885+hyperpolymath@users.noreply.github.com>
Co-authored-by: Claude Opus 5 <noreply@anthropic.com>

Author: hyperpolymath

.github/workflows/codeql.yml

@@ -28,7 +28,9 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - language: javascript-typescript
+          - language: actions
+            build-mode: none
+          - language: rust
             build-mode: none
     steps:
       - name: Checkout