fa6c0bedd3 refactor: Return uint64_t from GetSerializeSize (MarcoFalke)
fad0c8680e refactor: Use uint64_t over size_t for serialized-size values (MarcoFalke)
fa4f388fc9 refactor: Use fixed size ints over (un)signed ints for serialized values (MarcoFalke)
fa01f38e53 move-only: Move CBlockFileInfo to kernel namespace (MarcoFalke)
fa2bbc9e4c refactor: [rpc] Remove cast when reporting serialized size (MarcoFalke)
fa364af89b test: Remove outdated comment (MarcoFalke)
Pull request description:
Consensus code should arrive at the same conclusion, regardless of the architecture it runs on. Using architecture-specific types such as `size_t` can lead to issues, such as the low-severity [CVE-2025-46597](https://bitcoincore.org/en/2025/10/24/disclose-cve-2025-46597/).
The CVE was already worked around, but it may be good to still fix the underlying issue.
Fixes https://github.com/bitcoin/bitcoin/issues/33709 with a few refactors to use explicit fixed-sized integer types in serialization-size related code and concluding with a refactor to return `uint64_t` from `GetSerializeSize`. The refactors should not change any behavior, because the CVE was already worked around.
ACKs for top commit:
Crypt-iQ:
crACK fa6c0bedd3
l0rinc:
ACK fa6c0bedd3
laanwj:
Code review ACK fa6c0bedd3
Tree-SHA512: f45057bd86fb46011e4cb3edf0dc607057d72ed869fd6ad636562111ae80fea233b2fc45c34b02256331028359a9c3f4fa73e9b882b225bdc089d00becd0195e
