CI: compile packwiz on runner via go install (fixes glibc mismatch)

Drop the committed packwiz binary (built against glibc 2.34, incompatible
with the runner's node:20-bullseye / glibc 2.31). Instead fetch Go into
the image and 'go install github.com/packwiz/packwiz@latest' so it links
against the runner's glibc. Keeps the working inline git clone + tag-gated
release.

.gitea/workflows/build-pack.yaml

@@ -9,13 +9,18 @@ jobs:
   build:
     runs-on: docker
     steps:
-      - name: Environment check
+      - name: Install Go
         run: |
-          echo "cwd: $(pwd)"
-          echo "GITHUB_WORKSPACE: ${GITHUB_WORKSPACE}"
-          python3 --version; git --version 2>/dev/null || echo "git: MISSING"
-          curl --version 2>/dev/null | head -1 || echo "curl: MISSING"
-          tar --version 2>/dev/null | head -1 || echo "tar: MISSING"
+          GO_VER=1.22.5
+          curl -sSL "https://go.dev/dl/go${GO_VER}.linux-amd64.tar.gz" -o /tmp/go.tgz
+          tar -C /usr/local -xzf /tmp/go.tgz
+          /usr/local/go/bin/go version
+
+      - name: Install packwiz
+        run: /usr/local/go/bin/go install github.com/packwiz/packwiz@latest
+
+      - name: Add packwiz to PATH
+        run: echo "$(/usr/local/go/bin/go env GOPATH)/bin" >> "$GITHUB_PATH"
 
       - name: Fetch sources
         run: |
@@ -30,7 +35,7 @@ jobs:
 
       - name: Refresh index
         working-directory: client_pack
-        run: ../tools/packwiz refresh
+        run: packwiz refresh
 
       - name: Integrity check
         working-directory: client_pack
@@ -42,11 +47,11 @@ jobs:
 
       - name: Export client Modrinth pack
         working-directory: client_pack
-        run: ../tools/packwiz modrinth export -o ../FKRPG-${GITHUB_REF_NAME}.mrpack --restrictDomains=false
+        run: packwiz modrinth export -o ../FKRPG-${GITHUB_REF_NAME}.mrpack --restrictDomains=false
 
       - name: Refresh server index
         working-directory: server_pack
-        run: ../tools/packwiz refresh
+        run: packwiz refresh
 
       - name: Integrity check (server)
         working-directory: server_pack
@@ -58,7 +63,7 @@ jobs:
 
       - name: Export server Modrinth pack
         working-directory: server_pack
-        run: ../tools/packwiz modrinth export -o ../FKRPG-SERVER-${GITHUB_REF_NAME}.mrpack --restrictDomains=false
+        run: packwiz modrinth export -o ../FKRPG-SERVER-${GITHUB_REF_NAME}.mrpack --restrictDomains=false
 
       - name: Release
         if: startsWith(github.ref, 'refs/tags/v')