ci: add Gitea Actions workflow ported from .gitlab-ci.yml

.gitea/workflows/ci.yml

@@ -0,0 +1,42 @@
+# CI on the self-hosted Gitea, ported from .gitlab-ci.yml during the move off
+# GitLab (2026-09-22). Gitea reads .gitea/workflows and ignores .github/ once
+# this directory exists; .github/workflows stays as it was for GitHub.
+#
+# Every job runs in an image pinned by digest (tag in the trailing comment),
+# and the only action used is coffey-labs/actions/checkout pinned by SHA. The
+# instance resolves short `uses:` against itself, never GitHub, so nothing
+# unreviewed can be pulled in.
+#
+# Not ported, as on GitLab: publish.yml and release.yml still need doing.
+name: ci
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build:
+    runs-on: docker
+    container:
+      image: rust:1-bookworm@sha256:93ce27a88655056a51dbdd8f5f2d7ddc071c7b0070fb288a37b5a285fc83971e # 1-bookworm
+    # Both kept inside the workspace (a per-job volume on the project disk),
+    # deliberately not on /tmp, which on this host is a tmpfs that a Rust
+    # build of this size has filled before. There is no cache between runs
+    # here -- the runner's cache server is off -- so every build is cold.
+    env:
+      CARGO_INCREMENTAL: "0"
+    steps:
+      - uses: coffey-labs/actions/checkout@fab0c4d45e0162963965f1555df27b7bed5e20ec
+      - run: |
+          echo "CARGO_HOME=$GITHUB_WORKSPACE/.cargo" >> "$GITHUB_ENV"
+          echo "CARGO_TARGET_DIR=$GITHUB_WORKSPACE/target" >> "$GITHUB_ENV"
+      - run: apt-get update -qq && apt-get install -y -qq --no-install-recommends clang >/dev/null
+      - run: cargo build -p inbuxa --locked
+      # --no-run: the workflow compiled every test target without running them,
+      # which catches a test that no longer builds without paying for the suite.
+      - run: cargo test --workspace --locked --no-run

.gitignore

@@ -10,6 +10,7 @@ run.sh
 !.gitattributes
 !.github
 !.gitlab-ci.yml
+!.gitea
 CLAUDE.md
 
 # The cutover rehearsal writes its fixture and state here.