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-sandbox/src/docker.rs

@@ -3,9 +3,7 @@
 //! same API via `DOCKER_HOST`.
 
 use bollard::exec::{CreateExecOptions, ResizeExecOptions, StartExecResults};
-use bollard::models::{
-    ContainerCreateBody, HostConfig, Mount, MountTypeEnum, MountVolumeOptions,
-};
+use bollard::models::{ContainerCreateBody, HostConfig, Mount, MountTypeEnum, MountVolumeOptions};
 use bollard::query_parameters::{
     CreateContainerOptions, InspectContainerOptions, RemoveContainerOptions, StartContainerOptions,
 };
@@ -236,7 +234,11 @@ impl SandboxDriver for DockerDriver {
                 &handle.id,
                 CreateExecOptions {
                     cmd: Some(cmd.iter().map(|s| s.to_string()).collect()),
-                    env: if env.is_empty() { None } else { Some(env.to_vec()) },
+                    env: if env.is_empty() {
+                        None
+                    } else {
+                        Some(env.to_vec())
+                    },
                     attach_stdin: Some(true),
                     attach_stdout: Some(true),
                     attach_stderr: Some(true),
@@ -276,9 +278,9 @@ impl SandboxDriver for DockerDriver {
                     input,
                 })
             }
-            StartExecResults::Detached => {
-                Err(SandboxError::Engine("pty exec detached unexpectedly".into()))
-            }
+            StartExecResults::Detached => Err(SandboxError::Engine(
+                "pty exec detached unexpectedly".into(),
+            )),
         }
     }