core: Fix ps command truncating strings longer than 256 bytes

[cheese-cakee]

Fixes #4857

The ps command and its variants truncate strings longer than 256 bytes because they depend on core->blocksize. This PR decouples string reading from the static block by switching to RzBuffer for dynamic streaming reads.

Changes

• Replace const ut8 *buffer with RzBuffer *buffer and add ut64 offset field in RzStrStringifyOpt
• Rewrite
  z_str_stringify_raw_buffer to use
  z_buf_read_at in small chunks instead of requiring a contiguous memory pointer
• Update all ps handlers in cmd_print.c to create bounded RzBuffer wrappers
• Add NULL checks on all
  z_buf_new_with_pointers return values
• Add regression test for strings longer than 256 bytes in est/db/cmd/cmd_ps

[cheese-cakee]

done

[notxvilka]

This change is unnecessary, undo this and define variables in-place, like it was before. We use C99 standard, after all.

[notxvilka]

Same here, it's unnecessary, move it back.

[notxvilka]

See many compilation errors:

 clang -Ilibrz/util/librz_util.so.0.9.0.p -I. -I.. -Ilibrz -I../librz -Ilibrz/include -I../librz/include -Isubprojects/rzheap -I../subprojects/rzheap -Ilibrz/util/sdb/src -I../librz/util/sdb/src -Isubprojects/pcre2-10.47 -I../subprojects/pcre2-10.47 -I../subprojects/pcre2-10.47/src -I../subprojects/softfloat/include -Isubprojects/zlib-1.3.1 -I../subprojects/zlib-1.3.1 -I../subprojects/xz-5.8.1/src/liblzma/api -fdiagnostics-color=always -fsanitize=address,undefined -fno-omit-frame-pointer -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch -Werror -O2 -g -DCC_SUPPORTS_W_ENUM_CONVERION -DCC_SUPPORTS_W_ENUM_COMPARE -std=gnu99 -Werror=sizeof-pointer-memaccess -fvisibility=hidden -DRZ_PLUGIN_INCORE=1 -shared-libasan -DSUPPORTS_PCRE2_JIT -DZYDIS_STATIC_BUILD -msse2 -D_GNU_SOURCE -DASAN=1 -DRZ_ASSERT_STDOUT=1 -fno-sanitize=function -fPIC -DLZMA_API_STATIC -pthread -MD -MQ librz/util/librz_util.so.0.9.0.p/alloc.c.o -MF librz/util/librz_util.so.0.9.0.p/alloc.c.o.d -o librz/util/librz_util.so.0.9.0.p/alloc.c.o -c ../librz/util/alloc.c
In file included from ../librz/util/alloc.c:4:
In file included from ../librz/include/rz_util.h:68:
../librz/include/rz_util/rz_str.h:280:25: error: redefinition of typedef 'RzBuffer' is a C11 feature [-Werror,-Wtypedef-redefinition]
  280 | typedef struct rz_buf_t RzBuffer;
      |                         ^
../librz/include/rz_util/rz_buf.h:18:25: note: previous definition is here
   18 | typedef struct rz_buf_t RzBuffer;
      |                         ^
1 error generated.

And more: https://github.com/rizinorg/rizin/actions/runs/22780588559/job/66129877540?pr=5997

[notxvilka]

Use the PR template!