fix(#3245): resolve the remaining intra-doc links in hive-c0re

Takes the crate from 26 rustdoc warnings to 1, on top of the ten in the
previous commit.

argus's review findings:
- agent_sockets.rs: [`write`] was still ambiguous (function vs macro).
  The previous change narrowed the qualifier and left the ambiguity;
  [`write()`] is what resolves it.
- forge/users.rs <hex> and stats/container_stats.rs <name>: unclosed
  HTML tags in prose, now backticked.

The rest of the crate, so the count actually reaches zero:
- job_queue/mod.rs: Queue::graph_snapshot -> JobQueue::graph_snapshot
  (there is no Queue type), and super::scheduler -> scheduler (mod.rs
  *is* job_queue, so super:: pointed outside it)
- job_queue/resource.rs: NodeKind -> super::model::NodeKind
- matrix.rs: password_path(name) -> password_path; and
  forge::provision_user_token -> crate::forge::provision_user_token.
  Note the path has no `users` segment: forge/mod.rs declares `mod
  users` private and re-exports it, so the canonical path comes from the
  re-export rather than the directory tree.
- socket_server/lifecycle_handlers.rs: InfraContainer ->
  hive_priv_sock::InfraContainer
- stats/otel_metrics.rs: crate::meta::otel_config is a private fn no
  path can name from another module, so it becomes prose
- main.rs: redundant explicit link target dropped

coordinator.rs:405 (CrashWatchGuard) is deliberately untouched: #3244
deletes that doc block, so fixing it here would conflict with an open PR
and repair a symbol that is about to stop existing.

hive-c0re/src/socket_server/lifecycle_handlers.rs

@@ -53,7 +53,7 @@ pub(super) async fn handle_restart(coord: &Arc<Coordinator>, agent: &str, name:
 
 /// Restart a hive infrastructure container on behalf of an agent that
 /// holds the `infra_admin` capability. The `container` is already a valid
-/// [`InfraContainer`] (the caller parsed it); this gates on the capability
+/// [`hive_priv_sock::InfraContainer`] (the caller parsed it); this gates on the capability
 /// and routes the systemctl restart through hive-priv. Direct, not
 /// approval-gated.
 async fn handle_restart_infra(