139499: kvserver: reject leader lease proposals if leader is unknown r=iskettaneh a=iskettaneh

This commit rejects leader lease acquisition if the leader is unknown. Note that we have a cluster setting that does that regardless of the lease type (kv.lease.reject_on_leader_unknown.enabled). However, that cluster setting is set to default false since it caused performance regressions for epoch-based leases.

Fixes: #139498

Release note: None

139563: kvfollowerreadsccl: deflake TestBoundedStalenessDataDriven r=miraradeva a=miraradeva

This test has had a history of rare flakes where a follower read succeeds, instead of being routed to the leaseholder, due to environment slowness.

This commit skips the test under deadlock and allocates more resources for the default execution.

Fixes: #138121

Release note: None

139611: pgx: Migrate easily convertible cases to v5 r=spilchen a=spilchen

Currently, our codebase uses a mix of jackc/pgx versions, with some areas relying on v4 and others on v5. The goal is to fully migrate to v5. This commit updates all the straightforward cases to use v5.

The changes were made using a sed script for consistency. Some v4 usages remain, as they require additional modifications to migrate to v5. These will be addressed in a follow-up commit. This commit focuses solely on mechanical changes to keep the review process simple.

Epic: none
Release note: none

Informs #137595

139640: ui: bump cluster-ui to 25.1.0-prerelease.0 r=nkodali a=nkodali

Release note: None

139656: kvserver: enable verbose logging on flaky flow integration tests r=pav-kv a=kvoli

Verbose raft logging is enabled on the following tests:

```
TestFlowControlRangeSplitMergeV2
TestFlowControlAdmissionPostSplitMergeV2
TestFlowControlRaftSnapshotV2
TestFlowControlRaftMembershipRemoveSelfV2
```

Informs: #137510
Informs: #138103
Release note: None

139664: raft: make TestCommit test a real scenario  r=hakuuww a=pav-kv

This PR fixes `TestCommit`:

- the node must `becomeLeader()` in order to call `maybeCommit()`
- the node can not have higher-term entries in the log
- the node appends a dummy entry when it becomes leader

It also enhances the test so that it has log entries both in storage and in `unstable`.

Related to #137826

Co-authored-by: Ibrahim Kettaneh <[email protected]>
Co-authored-by: Mira Radeva <[email protected]>
Co-authored-by: Matt Spilchen <[email protected]>
Co-authored-by: Namrata Kodali <[email protected]>
Co-authored-by: Austen McClernon <[email protected]>
Co-authored-by: Pavel Kalinnikov <[email protected]>