Sanitize metadata image names in generated r2 script output

[trufae]

Motivation

• Prevent command/script injection in generated radare2 scripts by sanitizing metadata-derived image names before embedding them in emitted r2 flag/comment commands.

Description

• Call r_name_filter(im, -1) when im is non-NULL in emit_r2_method so image names read from metadata are filtered prior to any printf that emits f or CCu commands; the change is limited to src/main.c and preserves existing output for valid names.

Testing

• Attempted make -j4 in the container but the build failed due to missing radare2 development headers (missing r_util.h), so a full build/test could not be executed.

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Codex Task