* website: update `scaling` and `policy` blocks documentation

* website: hclfmt examples in scaling block docs

Update the ingress gateway documentation to remove the note stating
that a port must be specified for values in the `hosts` field when
the ingress gateway is listening on a non-standard HTTP port.

Specifying a port was required in Consul 1.8.0, but that requirement
was removed in 1.8.1 with hashicorp/consul#8190 which made Consul
include the port number when constructing the Envoy configuration.

Related Consul docs PR: hashicorp/consul#10827

Using `bridge` networking requires that you have CNI plugins installed
on the client, but this isn't in the jobspec `network` docs which are
the first place someone will look when trying to configure task
networking.

This PR implements a new "System Batch" scheduler type. Jobs can
make use of this new scheduler by setting their type to 'sysbatch'.

Like the name implies, sysbatch can be thought of as a hybrid between
system and batch jobs - it is for running short lived jobs intended to
run on every compatible node in the cluster.

As with batch jobs, sysbatch jobs can also be periodic and/or parameterized
dispatch jobs. A sysbatch job is considered complete when it has been run
on all compatible nodes until reaching a terminal state (success or failed
on retries).

Feasibility and preemption are governed the same as with system jobs. In
this PR, the update stanza is not yet supported. The update stanza is sill
limited in functionality for the underlying system scheduler, and is
not useful yet for sysbatch jobs. Further work in #4740 will improve
support for the update stanza and deployments.

Closes #2527

Current efs driver does not support telling it if its a `node` or a `controller`, and it will not print any error it will just ignore all other parameters then:(
So this will result in endpoint being `/tmp/csi.sock` and not `/csi/csi.sock` which will in turn break nomad/csi integration.

Also I changed the latest image tag to v1.3.2 to make sure anybody copy pasting this example is sure that it will work.

Tested on nomad 1.1.2

* add some more context to the recommendations
* add recommendations around per-AZ `plugin_id`

This PR fixes the API to _not_ set the default mesh gateway mode. Before,
the mode would be set to "none" in Canonicalize, which is incorrect. We
should pass through the empty string so that folks can make use of Consul
service-defaults Config entries to configure the default mode.

This PR implements first-class support for Nomad running Consul
Connect Mesh Gateways. Mesh gateways enable services in the Connect
mesh to make cross-DC connections via gateways, where each datacenter
may not have full node interconnectivity.

Consul docs with more information:
https://www.consul.io/docs/connect/gateways/mesh-gateway

The following group level service block can be used to establish
a Connect mesh gateway.

service {
  connect {
    gateway {
      mesh {
        // no configuration
      }
    }
  }
}

Services can make use of a mesh gateway by configuring so in their
upstream blocks, e.g.

service {
  connect {
    sidecar_service {
      proxy {
        upstreams {
          destination_name = "<service>"
          local_bind_port  = <port>
          datacenter       = "<datacenter>"
          mesh_gateway {
            mode = "<mode>"
          }
        }
      }
    }
  }
}

Typical use of a mesh gateway is to create a bridge between datacenters.
A mesh gateway should then be configured with a service port that is
mapped from a host_network configured on a WAN interface in Nomad agent
config, e.g.

client {
  host_network "public" {
    interface = "eth1"
  }
}

Create a port mapping in the group.network block for use by the mesh
gateway service from the public host_network, e.g.

network {
  mode = "bridge"
  port "mesh_wan" {
    host_network = "public"
  }
}

Use this port label for the service.port of the mesh gateway, e.g.

service {
  name = "mesh-gateway"
  port = "mesh_wan"
  connect {
    gateway {
      mesh {}
    }
  }
}

Currently Envoy is the only supported gateway implementation in Consul.
By default Nomad client will run the latest official Envoy docker image
supported by the local Consul agent. The Envoy task can be customized
by setting `meta.connect.gateway_image` in agent config or by setting
the `connect.sidecar_task` block.

Gateways require Consul 1.8.0+, enforced by the Nomad scheduler.

Closes #9446

add a section about memory oversubscription
Co-authored-by: Tim Gross <tgross@hashicorp.com>

when troubleshooting it is better if this command will actually work (pointing to a real repository)

* update docs

* document memory_oversubscription_enabled scheduler config

Add new `access_mode`/`attachment_mode` fields. Make it more clear which set
of fields belong to create vs register. Update the example spec that's
generated by `volume init`.

This PR adds the common OSS changes for adding support for Consul Namespaces,
which is going to be a Nomad Enterprise feature. There is no new functionality
provided by this changeset and hopefully no new bugs.

Add a `PerAlloc` field to volume requests that directs the scheduler to test
feasibility for volumes with a source ID that includes the allocation index
suffix (ex. `[0]`), rather than the exact source ID.

Read the `PerAlloc` field when making the volume claim at the client to
determine if the allocation index suffix (ex. `[0]`) should be added to the
volume source ID.

In a deployment with two groups (ex. A and B), if group A's canary becomes
healthy before group B's, the deadline for the overall deployment will be set
to that of group A. When the deployment is promoted, if group A is done it
will not contribute to the next deadline cutoff. Group B's old deadline will
be used instead, which will be in the past and immediately trigger a
deployment progress failure. Reset the progress deadline when the job is
promotion to avoid this bug, and to better conform with implicit user
expectations around how the progress deadline should interact with promotions.

HCL2 locals don't have type constraints, and the map syntax is interpreted as
an object. So users may need to explictly convert to map for some functions.

The `convert` function documentation was missing the required type constructor
parameter for collections.

Block labels are not expressions so they can't be interpolated without hacks
like `dynamic` blocks. Clarify this so that we don't confuse users who
shouldn't need to dig into the subtle nuances between expressions and blocks.

Using the environment variable stopped working here a while back,
should be using the port label. Also upgrade to uuid-api:v5 which
supports linux/arm64.

Since [mounts](https://www.nomadproject.io/docs/drivers/docker#mounts) is deprecated,
switch to newer `mount` in `task.config` for `docker` driver.

This PR enables jobs configured with a custom sidecar_task to make
use of the `service.expose` feature for creating checks on services
in the service mesh. Before we would check that sidecar_task had not
been set (indicating that something other than envoy may be in use,
which would not support envoy's expose feature). However Consul has
not added support for anything other than envoy and probably never
will, so having the restriction in place seems like an unnecessary
hindrance. If Consul ever does support something other than Envoy,
they will likely find a way to provide the expose feature anyway.

Fixes #9854