The task runner prestart hooks take a `joincontext` so they have the
option to exit early if either of two contexts are canceled: from
killing the task or client shutdown. Some tasks exit without being
shutdown from the server, so neither of the joined contexts ever gets
canceled and we leak the `joincontext` (48 bytes) and its internal
goroutine. This primarily impacts batch jobs and any task that fails
or completes early such as non-sidecar prestart lifecycle tasks.
Cancel the `joincontext` after the prestart call exits to fix the
leak.

The `go-getter` library was updated to 1.5.9 in #11481 to pick up a
bug fix for automatically unpacking uncompressed tar archives. But
this version had a regression in git `ref` param behavior and was
patched in 1.5.10.

Adds a package `scheduler/benchmarks` with some examples of profiling
and benchmarking the scheduler, along with helpers for loading
real-world data for profiling.

This tooling comes out of work done for #11712. These test benchmarks
have not been added to CI because these particular profiles are mostly
examples and the runs will add an excessive amount of time to CI runs
for code that rarely changes in a way that has any chance of impacting
performance.

fix: redirects website `/home` to `/`

When the scheduler picks a node for each evaluation, the
`LimitIterator` provides at most 2 eligible nodes for the
`MaxScoreIterator` to choose from. This keeps scheduling fast while
producing acceptable results because the results are binpacked.

Jobs with a `spread` block (or node affinity) remove this limit in
order to produce correct spread scoring. This means that every
allocation within a job with a `spread` block is evaluated against
_all_ eligible nodes. Operators of large clusters have reported that
jobs with `spread` blocks that are eligible on a large number of nodes
can take longer than the nack timeout to evaluate (60s). Typical
evaluations are processed in milliseconds.

In practice, it's not necessary to evaluate every eligible node for
every allocation on large clusters, because the `RandomIterator` at
the base of the scheduler stack produces enough variation in each pass
that the likelihood of an uneven sprea...

* Mesh Gateway doc enhancements

1. I believe this line should be corrected to add mesh as one of the choices
2. I found that we are not setting this meta, and it is a required element for wan federation. I believe it would be helpful and potentially time saving to note that right here.

clickable links in allocations chart

Add Allocation Filters in Client View

Add filters to Allocations

Co-authored-by: Luiz Aoqui <luiz@hashicorp.com>

cli: return error from raft commands if db is open

Before this change trying to run `nomad operator raft {info,logs}` on an
inuse raft.db would cause the command to block until the agent using
raft.db is closed.

After this change the command will block for 1s before returning a
(hopefully) helpful error message.

This change also sets the ReadOnly mode on the underlying BoltDb to
ensure diagnostics make no changes to the underlying store. We have no
evidence this has ever occurred, but it seems like a useful safety
measure.

No changelog added since this is a minor tweak in a "new" feature (it
was hidden in previous relases).

The `nomad operator raft logs` command uses a raft helper that reads
in the logs from raft and serializes them to JSON. The previous
implementation returned the slice of all logs and then serializes the
entire object. Update the helper to stream the log entries and then
serialize them as newline-delimited JSON.

The `nomad operator raft` and `nomad operator snapshot state`
subcommands for inspecting on-disk raft state were hidden and
undocumented. Expose and document these so that advanced operators
have support for these tools.

Use the new filtering and pagination capabilities of the `Eval.List`
RPC to provide filtering and pagination at the command line.

Also includes note that `nomad eval status -json` is deprecated and
will be replaced with a single evaluation view in a future version of
Nomad.