fix(ci): install jq in the container so the Trope IR test actually runs

[hyperpolymath]

CI / required is the last red check on main. After #31 fixed the version
assert, the job got two steps further and now fails at Validate repository
contracts with exit code 2 and one line of output:

jq is required

Root cause

tests/check-examples.sh:15:

command -v jq >/dev/null || { echo "jq is required"; exit 2; }

The pinned idris2-pack image does not ship jq. So the Trope IR conformance
test — the one asserting every example lowers to valid Trope IR — has never
actually executed in CI. It bailed before testing anything.

That makes this more than a build fix: it turns a step that always died early
into one that genuinely exercises the language's core guarantee.

Fix

Same class of problem as the missing xz in #28, so the step now handles both:
collect what is absent, install in a single apt-get pass, print both versions
so the log records what ran. A no-op on images that already have them.

Verified locally against origin/main (d29f89e)

bash -n over tests/ scripts/ ............... all parse
tests/check-examples.sh .................... exit 0  → "examples: all lower to valid Trope IR"
tests/aspect_tests.sh ...................... exit 0  → PASS=3 FAIL=0 WARN=0
scripts/check-root-shape.sh ................ exit 0  → 45 entries, 46 permitted
tests/workflows/validate_workflows_test.sh . exit 0  → Workflow validation PASSED

Note check-examples.sh skips the verdict round-trip when no sibling
tropecheck binary is built — that part still needs trope-checker, and is
reported as a note, not a pass.

🤖 Generated with Claude Code

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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