Fix heap bins tcache from accessing invalid addresses on glibc 2.42

[B1ackCat]

Description

Fix for heap bins tcache accessing invalid addresses on glibc 2.42.
Also adding a sanity check to ensure only properly aligned tcache entry pointers are traversed.

With the current implementation, when parsing tcache bins, corrupted values in the entry array (e.g. 0x7000…) can be misinterpreted as valid pointers. This causes gdb to dereference invalid memory and the command fails.

The fix adds a simple ptrsize-alignment check before constructing a GlibcTcacheChunk.
Since real heap chunk pointers are always ptrsize-aligned, this prevents mis-parsing and avoids invalid memory accesses without affecting normal behavior.

Checklist

• My code follows the code style of this project.
• My change includes a change to the documentation, if required.
• If my change adds new code, adequate tests have been added.
• I have read and agree to the CONTRIBUTING document.

[github-actions]

🤖 Coverage update for 64ec7d7 🔴

	Old	New
Commit	ee605f9	64ec7d7
Score	71.0775%	71.0582% (-0.0193)

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[gordonmessmer]

@hugsy @Grazfather Please merge these changes. CI testing confirms that this change fixes the test failures I see on Fedora > 43.

gordonmessmer#3