[countersyncd]: Fix netlink fd leakage and deadlock issue

[Pterosaur]

What I did
Replace netlink library from neli to genetlink and netlink-*

Why I did it
The original neli has two issues: deadlock and fd leakage.

How I verified it
Check it via unittest and in the real platform

Details if related

[mssonicbld]

/azp run

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[Copilot]

Pull request overview

This PR replaces the neli netlink library with genetlink and netlink-* libraries to fix deadlock and file descriptor leakage issues in the countersyncd component. The changes involve significant refactoring of socket management, introduction of a shared utilities module, and updates to the reconnection strategy.

Key Changes

• Migrated from neli to genetlink, netlink-packet-core, netlink-packet-generic, and netlink-sys libraries
• Added new netlink_utils module for shared family/group resolution functionality
• Introduced SoftReconnect command that performs health-check-based reconnection vs forcing immediate reconnection
• Updated socket configuration path and increased health timeout from 10s to 60s

Reviewed changes

Copilot reviewed 7 out of 8 changed files in this pull request and generated 9 comments.

Show a summary per file

File	Description
crates/countersyncd/src/message/netlink.rs	Added new SoftReconnect command variant to the NetlinkCommand enum
crates/countersyncd/src/actor/netlink_utils.rs	New shared utilities module for netlink family/group resolution, avoiding code duplication
crates/countersyncd/src/actor/mod.rs	Registered the new netlink_utils module
crates/countersyncd/src/actor/data_netlink.rs	Replaced neli socket types with netlink-sys Socket, updated connection logic, added health-check reconnection, changed to raw recv syscalls
crates/countersyncd/src/actor/control_netlink.rs	Replaced neli types with netlink-sys, updated resolver to use shared utilities module
crates/countersyncd/Cargo.toml	Replaced neli dependency with genetlink and netlink-* crates, added libc dependency
Cargo.toml	Updated workspace dependencies to include new netlink libraries, upgraded binrw to 0.15.0
Cargo.lock	Reflected all dependency changes including removal of neli and addition of netlink libraries

Comments suppressed due to low confidence (1)

crates/countersyncd/src/actor/data_netlink.rs:691

• The condition on line 689 checks if size == 0 but this check is unreachable because it's inside a branch where size if size > 0. This dead code should be removed as it can never execute and creates confusion about the control flow.

                if size == 0 {
                    return Err(io::Error::new(
                        io::ErrorKind::UnexpectedEof,

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[mssonicbld]

/azp run

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Azure Pipelines successfully started running 1 pipeline(s).

[Copilot]

Pull request overview

Copilot reviewed 7 out of 8 changed files in this pull request and generated 14 comments.

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[mssonicbld]

/azp run

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Azure Pipelines successfully started running 1 pipeline(s).