swarm: ctx propagation; bmt fixes; pss generic notification framework (#17150)

* cmd/swarm: minor cli flag text adjustments

* swarm/api/http: sticky footer for swarm landing page using flex

* swarm/api/http: sticky footer for error pages and fix for multiple choices

* cmd/swarm, swarm/storage, swarm: fix  mingw on windows test issues

* cmd/swarm: update description of swarm cmd

* swarm: added network ID test

* cmd/swarm: support for smoke tests on the production swarm cluster

* cmd/swarm/swarm-smoke: simplify cluster logic as per suggestion

* swarm: propagate ctx to internal apis (#754)

* swarm/metrics: collect disk measurements

* swarm/bmt: fix io.Writer interface

  * Write now tolerates arbitrary variable buffers
  * added variable buffer tests
  * Write loop and finalise optimisation
  * refactor / rename
  * add tests for empty input

* swarm/pss: (UPDATE) Generic notifications package (#744)

swarm/pss: Generic package for creating pss notification svcs

* swarm: Adding context to more functions

* swarm/api: change colour of landing page in templates

* swarm/api: change landing page to react to enter keypress

swarm/network/stream/syncer_test.go

@@ -202,9 +202,12 @@ func testSyncBetweenNodes(t *testing.T, nodes, conns, chunkCount int, skipCheck
 		// here we distribute chunks of a random file into stores 1...nodes
 		rrFileStore := storage.NewFileStore(newRoundRobinStore(sim.Stores[1:]...), storage.NewFileStoreParams())
 		size := chunkCount * chunkSize
-		_, wait, err := rrFileStore.Store(io.LimitReader(crand.Reader, int64(size)), int64(size), false)
+		_, wait, err := rrFileStore.Store(ctx, io.LimitReader(crand.Reader, int64(size)), int64(size), false)
+		if err != nil {
+			t.Fatal(err.Error())
+		}
 		// need to wait cos we then immediately collect the relevant bin content
-		wait()
+		wait(ctx)
 		if err != nil {
 			t.Fatal(err.Error())
 		}