Encrypted DNS health, comparing a zone's views, --local everywhere

jarld checks the DoT and DoH listeners every 10 minutes as a client would (page, dashboard, jarl encrypted-dns health, jarl_encrypted_dns_up). The Compare views tab and jarl zone diff show what differs between a zone's views, with Use this version. --local works on unlinked zones. A changed certificates.dir is followed by encrypted DNS's tls statements. Sharing an already shared version replaces other views' overrides.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

CHANGELOG.md

@@ -6,6 +6,34 @@ All notable changes to Jarl are documented here. The format follows
 
 ## [Unreleased]
 
+### Added
+
+- Encrypted DNS health: jarld checks the DoT and DoH listeners every 10
+  minutes as a client would (the certificate is for the host name,
+  current and the one Jarl last wrote; a question gets an answer) and
+  says what is wrong: nothing listening, a firewall, the wrong or an
+  older certificate. On the Encrypted DNS page (Check now), the
+  dashboard, `jarl encrypted-dns health` and Prometheus
+  `jarl_encrypted_dns_up`.
+- Comparing a zone's views: the Compare views tab and `jarl zone diff`
+  show the names and types that differ between the views that have a
+  zone, linked or not, with "Use this version" to share one view's
+  version. `GET /zones/{zone}/compare`.
+
+### Changed
+
+- `--local` (and `"local": true`) works on zones that aren't linked too:
+  their records are local anyway. `--shared` there is still refused.
+- When `certificates.dir` changes, jarld points the `tls` statements
+  encrypted DNS wrote at the new place when it starts; named kept the old
+  copies before, which renewals no longer updated.
+
+### Fixed
+
+- Sharing a view's version of a name that was shared already (Use this
+  version on the shared side) didn't replace another view's override; it
+  said there was nothing to do.
+
 ## [0.5.0] - 2026-10-12
 
 ### Upgrading from 0.4