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/fuse/fuse_file.go

@@ -84,7 +84,7 @@ func (sf *SwarmFile) Attr(ctx context.Context, a *fuse.Attr) error {
 	a.Gid = uint32(os.Getegid())
 
 	if sf.fileSize == -1 {
-		reader, _ := sf.mountInfo.swarmApi.Retrieve(sf.addr)
+		reader, _ := sf.mountInfo.swarmApi.Retrieve(ctx, sf.addr)
 		quitC := make(chan bool)
 		size, err := reader.Size(quitC)
 		if err != nil {
@@ -104,7 +104,7 @@ func (sf *SwarmFile) Read(ctx context.Context, req *fuse.ReadRequest, resp *fuse
 	sf.lock.RLock()
 	defer sf.lock.RUnlock()
 	if sf.reader == nil {
-		sf.reader, _ = sf.mountInfo.swarmApi.Retrieve(sf.addr)
+		sf.reader, _ = sf.mountInfo.swarmApi.Retrieve(ctx, sf.addr)
 	}
 	buf := make([]byte, req.Size)
 	n, err := sf.reader.ReadAt(buf, req.Offset)