chore(cubesys): resolve 4 clippy -D warnings blocking the check gate

* commands.rs:819 — `cell.links().iter().copied().collect::<Vec<_>>()`
  replaced with `cell.links().to_vec()` (clippy: "calling to_vec() is
  both faster and more readable").

* commands.rs:991 — `while let Some(tok) = it.next()` loop over metatag
  tokens rewritten as a direct `for tok in it` (clippy: "this loop could
  be written as a for loop").

* store.rs:699 — `put_code_cell` (8 args) annotated with
  `#[allow(clippy::too_many_arguments)]` (argument count is inherent to
  the code-cell put API; splitting would add indirection without benefit).

* lib.rs:136 — `store_code_cell` (8 args) annotated identically; this is
  the shared implementation every front-end uses so the count cannot change
  without redesigning the record-codec bridge.

Verification: ./check gate passes (fmt + tests + clippy -D warnings).

Co-Authored-By: Hermes Agent

cubesys/src/commands.rs

@@ -816,7 +816,7 @@ impl Session {
                     path,
                     Kind::Kernel,
                     cell.name().unwrap_or(path),
-                    &cell.links().iter().copied().collect::<Vec<_>>(),
+                    cell.links(),
                     &cell.code,
                     None,
                     None,
@@ -988,7 +988,7 @@ impl Session {
                 // Optional metatags: `doc_type=<t>` and/or `title=<t>` may
                 // follow. These are what `query <doc_type>` matches on.
                 let mut header = CubeHeader::new();
-                while let Some(tok) = it.next() {
+                for tok in it {
                     if let Some(v) = tok.strip_prefix("doc_type=") {
                         header.doc_type = Some(v.to_string());
                     } else if let Some(v) = tok.strip_prefix("title=") {

cubesys/src/lib.rs

@@ -133,6 +133,7 @@ pub fn load_code_cell<B: CubeBackend>(
 
 /// Build a [`CodeCell`] from parts and write it back as a record at `path`,
 /// so code written by the VM (or tooling) is visible to cubefs at that path.
+#[allow(clippy::too_many_arguments)]
 pub fn store_code_cell<B: CubeBackend>(
     store: &mut CubeStore<B>,
     path: &str,

cubesys/src/store.rs

@@ -696,6 +696,7 @@ impl ConcurrentStore {
     /// Store a code cell at `path` (the path->code bridge), durability-logged.
     /// `owner` (when set) is stamped on the record's `owner_local_user` field
     /// so owner enforcement (Task 6) can later reject cross-owner overwrites.
+    #[allow(clippy::too_many_arguments)]
     pub fn put_code_cell(
         &self,
         path: &str,