PR #97590 - sql: add metrics for prepared statement memory usage

[cockroach-teamcity]

Exalate commented:

Related PR: cockroachdb/cockroach#97590
Commit: cockroachdb/cockroach@aa31d92
Epic: none

---

Release note (ui change): Add the following new metrics to track memory
usage of prepared statements in sessions:

• sql.mem.internal.session.prepared.current
• sql.mem.internal.session.prepared.max-avg
• sql.mem.internal.session.prepared.max-count
• sql.mem.internal.session.prepared.max-max
• sql.mem.internal.session.prepared.max-p50
• sql.mem.internal.session.prepared.max-p75
• sql.mem.internal.session.prepared.max-p90
• sql.mem.internal.session.prepared.max-p99
• sql.mem.internal.session.prepared.max-p99.9
• sql.mem.internal.session.prepared.max-p99.99
• sql.mem.internal.session.prepared.max-p99.999
• sql.mem.sql.session.prepared.current
• sql.mem.sql.session.prepared.max-avg
• sql.mem.sql.session.prepared.max-count
• sql.mem.sql.session.prepared.max-max
• sql.mem.sql.session.prepared.max-p50
• sql.mem.sql.session.prepared.max-p75
• sql.mem.sql.session.prepared.max-p90
• sql.mem.sql.session.prepared.max-p99
• sql.mem.sql.session.prepared.max-p99.9
• sql.mem.sql.session.prepared.max-p99.99
• sql.mem.sql.session.prepared.max-p99.999

Jira Issue: DOC-7045