Fix CI: silence false-positive ShellCheck/EditorConfig findings

- podman-common.sh: file-wide shellcheck disable=SC2034 for its
  constants, which are intentionally defined for other scripts to
  source, not used within the file itself (ShellCheck can't see
  cross-file usage in that direction). Confirmed as the actual cause
  of the failing ShellCheck job via the real Gitea Actions log.
- podman-storage.sh: use the retry counter in cmd_unmount's log
  message instead of leaving it genuinely unused (real SC2034 hit,
  not a false positive).
- lint.yml: replace the editorconfig-checker/action-* marketplace
  action with a pinned, checksum-verified direct binary download —
  more robust than relying on third-party action resolution on
  self-hosted Gitea Actions runners — and disable its IndentSize
  check, which false-positives on Markdown's nested-list indentation
  and shell heredoc bodies. scripts/dev/lint.sh mirrors the same check
  for local use. All three lint.yml jobs verified passing locally.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

.github/workflows/lint.yml

@@ -48,6 +48,37 @@ jobs:
   editorconfig:
     name: EditorConfig
     runs-on: ubuntu-latest
+    # Installs the editorconfig-checker binary directly from its GitHub
+    # release instead of using the editorconfig-checker/action-* marketplace
+    # action: on self-hosted Gitea Actions runners, third-party action
+    # resolution can fail (observed as a 404 against the Gitea instance's
+    # own repo API while resolving the action) even with
+    # [actions].DEFAULT_ACTIONS_URL = github configured. A pinned, checksum
+    # -verified binary download has no such dependency on action resolution
+    # and works identically on GitHub-hosted and Gitea Actions runners.
+    env:
+      EC_VERSION: "3.8.0"
+      EC_SHA256: "5bda1d502d9a0bbd3caa0ef1d1e3b8ee496a18f226f69e0be06d24a0c8ae0237"
     steps:
       - uses: actions/checkout@v4
-      - uses: editorconfig-checker/action-editorconfig-checker@main
+
+      - name: Install editorconfig-checker
+        run: |
+          set -eu
+          curl -fL --retry 3 -o /tmp/ec.tar.gz \
+            "https://github.com/editorconfig-checker/editorconfig-checker/releases/download/v${EC_VERSION}/editorconfig-checker-linux-amd64.tar.gz"
+          echo "${EC_SHA256}  /tmp/ec.tar.gz" | sha256sum -c -
+          tar -xzf /tmp/ec.tar.gz -C /tmp
+          sudo install -m 0755 /tmp/editorconfig-checker /usr/local/bin/ec
+
+      - name: Run editorconfig-checker
+        # -disable-indent-size: this check wants every line's indentation to
+        # be an exact multiple of .editorconfig's indent_size (2), which
+        # produces false positives for prose content this repo legitimately
+        # has a lot of — Markdown's own nested-list indentation rules (3
+        # spaces under "- ", 4 under numbered items) don't align with a
+        # flat "multiple of 2" rule, and neither do many shell heredoc
+        # bodies or the XML comment blocks in plugin/podman.plg. The other
+        # checks (trailing whitespace, final newline, charset, line length)
+        # stay enabled and catch real issues.
+        run: ec -disable-indent-size