feat: Add Grafana auto-update & improve classifier

Add auto-update for Grafana on Synology via SSH + docker compose,
with review examples and a context.txt describing the specific setup
(Prometheus + Node Exporter, no plugins) so the classifier can
ignore plugin-only breaking changes.

The classifier now loads an optional context.txt per service to
tailor decisions to the actual deployment. It also truncates large
release notes intelligently, keeping important sections (breaking
changes, deprecations, migration notes) while dropping long PR
lists that add no signal.

test_classifier.py now also loads context.txt and accepts any
service name as argument.

services/grafana/review-examples/auto-1.txt

@@ -0,0 +1,25 @@
+action: auto
+reason: Patch release with security fixes, minor enhancements, and bug fixes. No breaking changes or manual steps required.
+---
+[Download page](https://grafana.com/grafana/download/12.4.2)
+[What's new highlights](https://grafana.com/docs/grafana/latest/whatsnew/)
+
+### Features and enhancements
+
+- **Analytics tab:** Improve voice over accessibility (Enterprise)
+- **Dashboards a11y:** Do not open time zonemenu on focus
+- **Dashboards:** Resolve display names by identity in version history
+- **Plugins:** Forward AWS SDK credential chain env vars to external AWS plugins
+- **Public Dashboards:** Prevent unintended CRUD operations from different orgs
+
+### Bug fixes
+
+- **IAM:** Handle NULL team_member.external column to fix dashboard loading
+- **Plugins:** Fix installer IsDisabled condition
+- **Plugins:** Forward PLUGIN_UNIX_SOCKET_DIR to plugin processes to fix tmp dir in restricted environments
+- **Security:** Fixes CVE-2026-27876
+- **Security:** Fixes CVE-2026-27877
+- **Security:** Fixes CVE-2026-28375
+- **Security:** Fixes CVE-2026-27879
+- **Security:** Fixes CVE-2026-27880
+- **Security:** Fixes CVE-2026-33375

services/grafana/review-examples/auto-2.txt

@@ -0,0 +1,18 @@
+action: auto
+reason: Security-only patch release. No breaking changes, no configuration changes, no manual steps required.
+---
+[Download page](https://grafana.com/grafana/download/12.3.6)
+[What's new highlights](https://grafana.com/docs/grafana/latest/whatsnew/)
+
+### Features and enhancements
+
+- **Public Dashboards:** Prevent unintended CRUD operations from different orgs
+
+### Bug fixes
+
+- **Security:** Fixes CVE-2026-27876
+- **Security:** Fixes CVE-2026-27877
+- **Security:** Fixes CVE-2026-28375
+- **Security:** Fixes CVE-2026-27879
+- **Security:** Fixes CVE-2026-27880
+- **Security:** Fixes CVE-2026-27876

services/grafana/review-examples/auto-3.txt

@@ -0,0 +1,20 @@
+action: auto
+reason: The only breaking change is about plugin environment variables, which does not affect a simple Prometheus + Node Exporter setup with no third-party plugins installed.
+---
+[Download page](https://grafana.com/grafana/download/12.4.0)
+[What's new highlights](https://grafana.com/docs/grafana/latest/whatsnew/)
+
+### Breaking changes
+
+- **Plugins:** Prevent passing host environment variables to plugin processes by default
+
+### Features and enhancements
+
+- **Alerting:** Add Alert Rules tabs navigation with feature toggle
+- **Dashboards:** Add ability to share dashboards externally
+- **Plugins:** Forward AWS SDK credential chain env vars to external AWS plugins
+
+### Bug fixes
+
+- **Dashboards:** Fix panel rendering issue with long time ranges
+- **Prometheus:** Fix label matching in metric browser

services/grafana/review-examples/manual-1.txt

@@ -0,0 +1,17 @@
+action: manual
+reason: Major version bump that removes the viewers_can_edit setting and changes anonymous auth enforcement. These configuration changes could affect dashboard access. Admin should review config before upgrading.
+---
+[Download page](https://grafana.com/grafana/download/12.0.0)
+[What's new highlights](https://grafana.com/docs/grafana/latest/whatsnew/)
+
+### Breaking changes
+
+- **Alerting:** Make $value return the query value in case when a single datasource is used
+- **Anonymous:** Enforce org role Viewer setting
+- **Config:** Removes setting `viewers_can_edit`
+- **Frontend:** Remove Angular (Enterprise)
+- **Chore:** Enabling failWrongDSUID by default in Grafana 12
+
+### Deprecations
+
+- **Alerting:** Deprecate OpsGenie integration

services/grafana/review-examples/manual-2.txt

@@ -0,0 +1,16 @@
+action: manual
+reason: Major version changes secret encryption so data source credentials created with v9+ cannot be decrypted by older versions. Rollback becomes difficult. Admin should back up the database before upgrading. Also changes log format which may affect monitoring.
+---
+[Download page](https://grafana.com/grafana/download/9.0.0)
+[What's new highlights](https://grafana.com/docs/grafana/latest/whatsnew/)
+
+### Breaking changes
+
+* Any secret (data sources credential, alert manager credential, etc, etc) created or modified with Grafana v9.0 won't be decryptable from any previous version (by default) because the way encrypted secrets are stored into the database has changed. Although secrets created or modified with previous versions will still be decryptable by Grafana v9.0.
+* If required, although generally discouraged, the `disableEnvelopeEncryption` feature toggle can be enabled to keep envelope encryption disabled once updating to Grafana v9.0.
+* In case of need to rollback to an earlier version of Grafana (i.e. Grafana v8.x) for any reason, after being created or modified any secret with Grafana v9.0, the `envelopeEncryption` feature toggle will need to be enabled to keep backwards compatibility.
+* Alternatively, backing up the Grafana database before updating could be a good idea to prevent disasters.
+
+The format of log messages have been updated, `lvl` is now `level` and `eror` and `dbug` has been replaced with `error` and `debug`. The precision of timestamps has been increased. To smooth the transition, it is possible to opt-out of the new log format by enabling the feature toggle `oldlog`. This option will be removed in a future minor release.
+
+The `Rename by regex` transformation has been improved to allow global patterns of the form `/<stringToReplace>/g`. Depending on the regex match used, this may cause some transformations to behave slightly differently.