Add verification note confirming that comprehensive tests for the
is_ssrf_blocked() method already exist and pass.
Tests cover:
- 4 positive test cases (code in data, message substring)
- 5 negative test cases (different codes, empty data, no data, case sensitivity)
- Boolean return value verification
- All 9 tests compile and execute successfully
Location: crates/pdftract-cli/src/mcp/framing/mod.rs (lines 707-779)
Closes bf-5ee1l
