Add smtlib-benchmark-finder agentic workflow (#9629)

Monthly agentic workflow that discovers community-contributed SMT-LIB
benchmark repositories on GitHub, excluding official distributions from
smtlib.org and Zenodo, and posts a categorised summary as a GitHub
Discussion.

## Workflow steps

- **Exclusion list** — scrapes `smtlib.cs.uiowa.edu` + paginates the
[Zenodo SMT-LIB community](https://zenodo.org/communities/smt-lib/) (up
to 300 records) to extract official repo URLs; hard-excludes `SMT-LIB/*`
and `SMT-Competition/*` orgs
- **GitHub search** — 7 search strategies (topic tags
`smtlib`/`smt-lib`/`smt2`, filename/path patterns, README mentions)
scoped to repos pushed since the last run (90-day window on first run)
- **Filter + classify** — removes official sets and noise (homework
repos, empty repos); categorises survivors into: solver evaluation,
verification, security/CTF, theory/logic, tool output, education, other
- **Discussion report** — posts `[SMT-LIB Benchmarks] Community
Benchmark Repository Survey — [Month YYYY]`; older discussions
auto-closed after 90 days
- **Cache** — stores classified repo sets and run date so subsequent
runs are incremental

## Files

- `.github/workflows/smtlib-benchmark-finder.md` — workflow definition
- `.github/workflows/smtlib-benchmark-finder.lock.yml` — compiled GitHub
Actions YAML (`gh aw compile`)

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>

.github/dependabot.yml

@@ -1,6 +1,8 @@
-version: 2
 updates:
-  - package-ecosystem: "github-actions"
-    directory: "/"
-    schedule:
-      interval: "weekly"
+- directory: /
+  ignore:
+  - dependency-name: "github/gh-aw-actions/**" # Managed by gh aw compile. Version-locked to the gh-aw compiler; do not bump.
+  package-ecosystem: github-actions
+  schedule:
+    interval: weekly
+version: 2