fix: feat: Woodpecker CI pipeline with ShellCheck + duplicate code detection (#45)

- Add .woodpecker/ci.yml: two-step pipeline (shellcheck + duplicate detection)
- Add .woodpecker/detect-duplicates.py: sliding-window hash detection (5-line
  windows, 2+ files) plus grep-based anti-pattern checks (hardcoded CI_STATE,
  hardcoded WOODPECKER_REPO_ID). Runs as failure: ignore so CI stays green
  while findings are visible in logs.
- Add .shellcheckrc: disable SC1090/SC1091 (dynamic source paths are
  intentional; all scripts use the same lib/env.sh pattern)
- Update projects/disinto.toml: woodpecker_repo_id = 4, remove bypass comment

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.shellcheckrc

@@ -0,0 +1,6 @@
+# .shellcheckrc — project-level ShellCheck configuration
+#
+# SC1090/SC1091: all scripts source lib/env.sh via a dynamic path
+#   (source "$(dirname "$0")/../lib/env.sh") — this is intentional.
+#   Individual source calls that should be checked use explicit directives.
+disable=SC1090,SC1091