89752: jobs/cdc: add metrics for paused jobs  r=miretskiy a=jayshrivastava

 This change adds new metrics to count paused jobs for every job type. For
  example, the metric for paused changefeed jobs is
  `jobs.changefeed.currently_paused`. These metrics are counted at an
  interval defined by the cluster setting `jobs.metrics.interval.poll`.
  
  This is implemented by a job which periodically queries `system.jobs`
  to count the number of paused jobs. This job is of the newly added type
  `jobspb.TypePollJobsStats`. When a node starts it's job registry, it will
  create an adoptable stats polling job if it does not exist already using a
  transaction.
  
  This change adds a test which pauses and resumes changefeeds while asserting
  the value of the `jobs.changefeed.currently_paused` metric. It also adds a
  logictest to ensure one instance of the stats polling job is created in a
  cluster.
  
  Resolves: #85467
  
  Release note (general change): This change adds new metrics to count
  paused jobs for every job type. For example, the metric for paused
  changefeed jobs is `jobs.changefeed.currently_paused`. These metrics
  are updated at an interval defined by the cluster setting
  `jobs.metrics.interval.poll`, which is defauled to 10 seconds.
  
  Epic: None


94633: kvserver: document reproposals r=nvanbenschoten a=tbg

Reproposals are a deep rabbit hole and an area in which past changes
were all related to subtle bugs. Write it all up and in particular make
some simplifications that ought to be possible if my understanding is
correct:

- have proposals always enter `(*Replica).propose` without a
  MaxLeaseIndex or prior encoded command set, i.e. `propose`
  behaves the same for reproposals as for first proposals.
- assert that after a failed call to tryReproposeWithNewLeaseIndex,
  the command is not in the proposals map, i.e. check absence of
  a leak.
- replace code that should be impossible to reach (and had me confused
  for a good amount of time) with an assertion.
- add long comment on `r.mu.proposals`.

This commit also moves `tryReproposeWithNewLeaseIndex` off `(*Replica)`,
which is possible due to recent changes[^1]. In doing so, I realized
there was a (small) data race (now fixed): when returning a
`NotLeaseholderError` from that method, we weren't acquiring `r.mu`. It
may have looked as though we were holding it already since we're
accessing `r.mu.propBuf`, however that field has special semantics - it
wraps `r.mu` and acquires it when needed.

[^1]: The "below raft" test mentioned in the previous comment was
changed in #93785 and
no longer causes a false positive.

Epic: CRDB-220
Release note: None


96650: kvserver: extract kvstorage.DestroyReplica r=pavelkalinnikov a=tbg

This series of commits extracts `(*Replica).preDestroyRaftMuLocked` into a
free-standing method `kvstorage.DestroyReplica`.

In doing so, it separates the in-memory and on-disk steps that are a part
of replica removal, and makes the on-disk steps unit testable.

Touches #93241.

Epic: CRDB-220
Release note: None


96659: sql: wrap stacktraceless errors with errors.Wrap r=andreimatei a=ecwall

Fixes #95794

This replaces the previous attempt to add logging here #95797.

The context itself cannot be augmented to add a stack trace to errors because
it interferes with grpc timeout logic - gRPC compares errors directly without
checking causes https://github.com/grpc/grpc-go/blob/v1.46.0/rpc_util.go#L833.
Although the method signature allows it, `Context.Err()` should not be
overriden to customize the error:
```
// If Done is not yet closed, Err returns nil.
// If Done is closed, Err returns a non-nil error explaining why:
// Canceled if the context was canceled
// or DeadlineExceeded if the context's deadline passed.
// After Err returns a non-nil error, successive calls to Err return the same error.
Err() error
```
Additionally, a child context of the augmented context may end up being used
which will circumvent the stack trace capture.

This change instead wraps `errors.Wrap` in a few places that might end up
helping debug the original problem:
1) Where we call `Context.Err()` directly.
2) Where gRPC returns an error after possibly calling `Context.Err()`
   internally or returns an error that does not have a stack trace.

Release note: None

96770: storage: don't modify the given cfg.Opts r=RaduBerinde a=RaduBerinde

This change improves the `NewPebble` code to not modify the given `cfg.Opts`. Such behavior is surprising and can trip up tests that reuse the same config.

Also, `ResolveEncryptedEnvOptions` and `wrapFilesystemMiddleware` no longer modify the `Options` directly; and `CheckNoRegistryFile` is now a standalone function.

Release note: None
Epic: none

96793: kvserver: de-flake TestReplicaProbeRequest r=pavelkalinnikov a=tbg

Chanced upon this failure mode in unrelated PR #96781.

Epic: none
Release note: None


Co-authored-by: Jayant Shrivastava <jayants@cockroachlabs.com>
Co-authored-by: Tobias Grieger <tobias.b.grieger@gmail.com>
Co-authored-by: Evan Wall <wall@cockroachlabs.com>
Co-authored-by: Radu Berinde <radu@cockroachlabs.com>