feat: implement complete tree-sitter-shellspec grammar with comprehensive testing

- Add full ShellSpec grammar extending tree-sitter-bash
- Support all ShellSpec constructs: Describe, Context, It, hooks, utilities
- Include Data block parsing with statements and argument styles
- Add 61 comprehensive test cases covering real-world patterns
- Implement optimized GitHub workflows with CI/CD automation
- Configure complete development tooling (linting, formatting, pre-commit)
- Add comprehensive documentation and contribution guidelines
- Optimize grammar conflicts to zero warnings
- Support editor integration for Neovim, VS Code, Emacs

Breaking Changes:
- Initial release, no previous API to break

BREAKING CHANGE: Initial implementation of tree-sitter-shellspec grammar

# Conflicts:
#	.github/workflows/codeql.yml
#	.github/workflows/pr-lint.yml
#	.pre-commit-config.yaml

# Conflicts:
#	.github/workflows/pr-lint.yml

# Conflicts:
#	.github/workflows/pr-lint.yml

test/spec/23.custom_matcher_spec.sh

@@ -0,0 +1,14 @@
+#shellcheck shell=sh
+
+# regexp custom matcher is defined in "support/custom_matcher.sh" and
+# imported by "spec_helper.sh"
+
+Describe 'custom matcher'
+  Describe 'regexp'
+    number() { echo 12345; }
+    It 'checks with regular expression'
+      When call number
+      The output should regexp '[0-9]*$'
+    End
+  End
+End