Add the #3314 CHANGELOG entry

[erikdarlingdata]

Adds the [Unreleased] / ### Fixed entry for #3314, whose fix merged as #3336 (10c40bc2). Lane PRs do not edit CHANGELOG.md, so the entry is spliced separately.

Two inserted lines: the entry at the top of ### Fixed and the [#3314] link definition. Anchored on the first ### Fixed at or after the [Unreleased] marker and asserted to land before ## [3.7.0]. CRLF preserved, zero bare LF.

[claude]

Reviewed. This is a doc-only CHANGELOG splice (2 lines: the ### Fixed entry for #3314 and its [#3314] link definition), no T-SQL, Lite, or Darling code changes — so no CONTRIBUTING.md style rules or Lite/Darling parity concerns apply here.

Checked:

• Placement: entry lands as the first ### Fixed item, consistent with the file's "most-recently-merged sits on top" ordering (the Reach the delivery cooldown through the control plane as delivery.cooldown_minutes #3336 fix that closes email_cooldown_minutes is the only throttle on Slack/Teams/PagerDuty delivery, but it is named for email, absent from get_alert_settings/update_alert_settings, and capped at 120 minutes #3314 is the tip of dev).
• No duplicate [#3314] reference or link definition elsewhere in the file; the link def is appended at the end of the reference list, matching the file's existing (insertion-order, not numeric) convention.
• Content accuracy: compared the entry's claims (column rename via write-only alias, per-table transactional write, the mcp role's column-level grant leaving SMTP password/webhook URLs/PagerDuty key/smtp_host unwritable, the unchanged 120-minute ceiling) against PR Reach the delivery cooldown through the control plane as delivery.cooldown_minutes #3336's description — all check out, nothing fabricated or overstated.

No correctness, security, or parity issues found.