Fix link consistency and add security note to setup guide

Fix relative link for tinytex-pattern-maintenance.md in
.claude/CLAUDE.md (missing ../ prefix). Add note about not
committing secrets to dev-docs/claude-code-setup.md.

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

Author: cderv

.claude/CLAUDE.md

@@ -205,7 +205,7 @@ Key phases:
 
 ### LaTeX Error Detection
 
-LaTeX error pattern maintenance is documented in [dev-docs/tinytex-pattern-maintenance.md](dev-docs/tinytex-pattern-maintenance.md).
+LaTeX error pattern maintenance is documented in [dev-docs/tinytex-pattern-maintenance.md](../dev-docs/tinytex-pattern-maintenance.md).
 
 - Patterns inspired by TinyTeX's comprehensive regex.json
 - Automated daily verification workflow checks for TinyTeX pattern updates

dev-docs/claude-code-setup.md

@@ -81,6 +81,8 @@ CLAUDE.local.md           # Personal overrides
 
 These stay personal to each developer.
 
+Avoid committing API keys, tokens, or credentials in any `.claude/` or `llm-docs/` file. Use environment variables or `.env` (also gitignored) for sensitive values.
+
 ## Further Reading
 
 - [Claude Code documentation](https://docs.anthropic.com/en/docs/claude-code)