CI: remove k8s stages, fix the Docker-level pipeline green

Survey + fixes so the pipeline passes at the Docker level (no k8s).

- Remove k8s: drop the `sandbox-k8s` job (kind/Calico/--features k8s-tests) and the
  "Helm chart lints" gate step. release.yml was already k8s-clean.
- Rust job:
  - `cargo fmt --all` — fix pre-existing formatting drift (fmt --check was failing).
  - clippy -D warnings: fix 3 lib warnings (cm-brain sort_by_key→Reverse, cm-api
    fleet.rs doc list indentation, node_rules map_or→is_none_or).
  - Regenerate the .sqlx offline cache (was missing the cm-runtime run_loop test
    query → offline compile failed). DB-backed tests use testcontainers at runtime.
  - Set SQLX_OFFLINE=true on the rust + e2e jobs so query! macros compile against
    the committed cache deterministically (no DB needed at compile time).
- Frontend job:
  - Fix the 1 ESLint error (useAgentTelemetry: no setState-synchronously-in-effect;
    tag the slice with agentId + derive null on mismatch).
  - Fix 2 stale panel-params tests (`terminal` is a valid app id now; assert the
    current APP_IDS + use a genuinely-unknown id for the reject case).

Verified locally: fmt clean, clippy --all-targets -D warnings clean (offline),
frontend lint 0 errors, tsc clean, 86/86 frontend tests pass, build OK.

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

crates/cm-topology/src/builders.rs

@@ -15,16 +15,28 @@ fn id(i: usize) -> String {
 
 fn star(n: usize, kind: EdgeKind) -> Vec<Edge> {
     (1..n)
-        .map(|i| Edge { from: id(0), to: id(i), kind })
+        .map(|i| Edge {
+            from: id(0),
+            to: id(i),
+            kind,
+        })
         .collect()
 }
 
 fn chain(n: usize, close: bool) -> Vec<Edge> {
     let mut edges: Vec<Edge> = (0..n.saturating_sub(1))
-        .map(|i| Edge { from: id(i), to: id(i + 1), kind: EdgeKind::PipesTo })
+        .map(|i| Edge {
+            from: id(i),
+            to: id(i + 1),
+            kind: EdgeKind::PipesTo,
+        })
         .collect();
     if close && n > 1 {
-        edges.push(Edge { from: id(n - 1), to: id(0), kind: EdgeKind::PipesTo });
+        edges.push(Edge {
+            from: id(n - 1),
+            to: id(0),
+            kind: EdgeKind::PipesTo,
+        });
     }
     edges
 }
@@ -33,7 +45,11 @@ fn complete(n: usize, kind: EdgeKind) -> Vec<Edge> {
     let mut edges = Vec::new();
     for i in 0..n {
         for j in (i + 1)..n {
-            edges.push(Edge { from: id(i), to: id(j), kind });
+            edges.push(Edge {
+                from: id(i),
+                to: id(j),
+                kind,
+            });
         }
     }
     edges