fix: address PR #9 review feedback quality-debt (#59)

- .markdownlint.json: enforce MD004 asterisk style to match project conventions
- .wiki/Contributing.md: convert all dash list markers to asterisks (MD004)
- .wiki/Coding-Standards.md: fix PHPDoc bullet wording (add missing preposition)
- build.sh: add set -euo pipefail for strict error handling
- build.sh: fix SC2115 (use ${var:?} to prevent rm -rf /)
- build.sh: fix SC2164 (cd build || exit 1)
- build.sh: fix SC2028 (use printf instead of echo for escape sequences)
- build.sh: fix SC2035 (use ./*.php glob to avoid dash-named files)

Closes #46

.wiki/Coding-Standards.md

@@ -67,7 +67,7 @@ if ($condition) {
 ### Documentation
 
 * All classes, methods, and functions should be documented using PHPDoc
-* Include a description, parameters, return values, and exceptions
+* Include a description of the parameters, return values, and possible exceptions
 
 ```php
 /**