[hardening] TBL load integer overflow + memory-safety cleanups

[Not4right]

Hardening patch set covering one critical finding (TBL load integer
overflow → out-of-bounds write on 32-bit flight targets) plus several
medium-severity defensive cleanups.

See the accompanying GitHub issue for the full writeup of the critical
finding and a conceptual reproducer.

Summary of changes

File	Why
cfe_tbl_passthru_codec.c	Guard Offset+NumBytes against unsigned overflow before size check.
cfe_tbl_eds_codec.c	Same overflow guard for the EDS codec.
cfe_tbl_load.c	Defense-in-depth overflow guard on size_t arithmetic.
cfe_tbl_internal.c	Replace UB-prone memchr+strcpy in MarkNameAsModified; add bounds and small-buffer guards.
cfe_es_mempool.c	Capture and log OS_MutSemTake/OS_MutSemGive failures (matches SB/FS/CDS convention).
cfe_es_cds.c, cfe_sb_priv.c	sprintf → snprintf (MISRA-C compliance and config-widening robustness).
osal/src/os/vxworks/src/os-impl-tasks.c	Clear lrec->heap_block immediately after free so dangling state is never observable.

Pre-merge checklist

• Run repo CI (CodeQL, cppcheck, format-check, unit-test-coverage).
• Add a unit test in cfe/modules/tbl/ut-coverage/ for the wrap-around case (Offset = 0xFFFFFFF0, NumBytes = 0x100).
• Validate against a 32-bit target build (RTEMS or VxWorks) — the bug only reproduces where size_t is 32 bits.
• CCB / cFS Product Team review.