ci: rework CI script for more extensibility

Rework script for more flexibility and extensibility:

* Run any command in a container with `--docker` or in the current
  environment without this parameter.
* Split compiling circuits and producing constraint & table, because
  further work with proof market requires the constraint only.
  Run each command as a separate step in CI.
* Use single script for all commands. New commands with the
  proof-market-toolchain will use the same syntax.

The new script syntax is heavily inspired by
https://github.com/NilFoundation/dbms/blob/master/scripts/ci.sh

Follow-up to #5

.github/workflows/main.yml

@@ -13,17 +13,17 @@ concurrency:
     format('{0}/{1}', github.workflow, github.ref) }}
   cancel-in-progress: true
 
-env:
-  SCRIPT_NAME: docker-run.sh
-
 jobs:
-  test-ll-workflow:
+  test-zkllvm-workflow:
     runs-on: ubuntu-22.04
 
     steps:
       - uses: actions/checkout@v3
         with:
           submodules: recursive
 
-      - name: Run the workflow script
-        run: scripts/${{ env.SCRIPT_NAME }}
+      - name: Compile a circuit
+        run: scripts/ci.sh --docker compile
+
+      - name: Make constraint and assignment table
+        run: scripts/ci.sh --docker run_assigner

scripts/ci.sh

@@ -0,0 +1,95 @@
+#!/usr/bin/env bash
+set -euxo pipefail
+
+# define dirs so that we can run scripts from any directory without shifting filesystem paths
+SCRIPT_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
+REPO_ROOT="$SCRIPT_DIR/.."
+
+# podman is a safer option for using on CI machines
+if ! command -v podman; then
+    DOCKER="docker"
+    DOCKER_OPTS=""
+else
+    DOCKER="podman"
+    DOCKER_OPTS='--detach-keys= --userns=keep-id'
+fi
+
+# checking files that should be produced
+# on all steps of the pipeline
+check_file_exists() {
+    FILE1="${1}"
+    if [ ! -e "$FILE1" ]
+    then
+        echo "File $FILE1 was not created" >&2
+        exit 1
+    else
+        echo "File $FILE1 created successfully"
+    fi
+}
+
+compile() {
+    if [ "$USE_DOCKER" = true ] ; then
+        cd "$REPO_ROOT"
+        $DOCKER run $DOCKER_OPTS \
+          --rm \
+          --platform=linux/amd64 \
+          --user $(id -u ${USER}):$(id -g ${USER}) \
+          --volume $(pwd):/opt/zkllvm-template \
+          ghcr.io/nilfoundation/zkllvm-template:latest \
+          sh -c "bash ./scripts/ci.sh compile"
+        cd -
+    else
+        rm -rf "$REPO_ROOT/build"
+        mkdir -p "$REPO_ROOT/build"
+        cd "$REPO_ROOT/build"
+        cmake -DCIRCUIT_ASSEMBLY_OUTPUT=TRUE ..
+        make template
+        cd -
+        check_file_exists "$REPO_ROOT/build/src/template.ll"
+    fi
+}
+
+run_assigner() {
+    if [ "$USE_DOCKER" = true ] ; then
+        cd "$REPO_ROOT"
+        $DOCKER run $DOCKER_OPTS \
+          --rm \
+          --platform=linux/amd64 \
+          --user $(id -u ${USER}):$(id -g ${USER}) \
+          --volume $(pwd):/opt/zkllvm-template \
+          ghcr.io/nilfoundation/zkllvm-template:latest \
+          sh -c "bash ./scripts/ci.sh run_assigner"
+        cd -
+    else
+        cd "$REPO_ROOT/build"
+        assigner \
+          -b src/template.ll \
+          -i ../src/main.inp \
+          -c template.crct \
+          -t template.tbl \
+          -e pallas
+        cd -
+        check_file_exists "$REPO_ROOT/build/template.crct"
+        check_file_exists "$REPO_ROOT/build/template.tbl"
+    fi
+  }
+
+
+USE_DOCKER=false
+SUBCOMMAND=run_all
+
+while [[ "$#" -gt 0 ]]; do
+    case $1 in
+        -d|--docker) USE_DOCKER=true ;;
+        all) SUBCOMMAND=run_all ;;
+        compile) SUBCOMMAND=compile ;;
+        run_assigner) SUBCOMMAND=run_assigner ;;
+        make_statement) SUBCOMMAND=make_statement ;;
+        prove) SUBCOMMAND=prove ;;
+        *) echo "Unknown parameter passed: $1"; exit 1 ;;
+    esac
+    shift
+done
+
+echo "Running ${SUBCOMMAND}"
+$SUBCOMMAND