feat: update AI automation agents, add reviewer agent, fix leaks, enhance CI

Agents:
- cmake-expert: fix stale CMake version (4.1 -> 3.22), add OpenSSL/xxHash deps
- integrator: fix stale test.py references to tests/integration/, update CI docs
- test-writer: update integration test patterns for modular test structure
- reviewer: new comprehensive PR reviewer (code, build, CI, docs, quality)

Bug fixes:
- delta.c: set instructions[i].type = DELTA_INSTR_LITERAL in deserialize
- scanner.c: free ArrayList when directory_scanner_next returns NULL

CI:
- Add sanitizer job (ASan + UBSan) that catches real leaks
- Add clang-tidy job with proper warning/error detection
- Remove || true masking (fixes now make sanitizer useful)

src/shared/delta.c

@@ -376,6 +376,7 @@ Delta *delta_deserialize(const Data *data) {
         free(delta);
         return NULL;
       }
+      delta->instructions[i].type = DELTA_INSTR_LITERAL;
       memcpy(&delta->instructions[i].literal.length, buf + pos, sizeof(uint32_t));
       pos += sizeof(uint32_t);