ci: replace linting setup with flint (#1883)

## Summary

- Replace the custom super-linter setup with
[flint](https://github.com/grafana/flint) v0.4.0, which provides shared,
maintained lint tasks (super-linter, link checking, renovate-deps)
- Use flint's Renovate shareable preset for custom managers instead of
inline config
- Remove manual URL remap step from lint workflow (now handled by
flint's links.sh)
- Add `lint:renovate-deps` task to verify tracked Renovate dependencies
- Move release-please config and manifest into `.github/config/`
- Add PR title linting workflow (`action-semantic-pull-request`)

## Test plan

- [ ] CI passes (lint, build, tests)
- [ ] Release-please workflow still triggers correctly with moved config
- [ ] PR title lint workflow runs on new PRs

---------

Signed-off-by: Gregor Zeitlinger <gregor.zeitlinger@grafana.com>

Author: zeitlinger

.editorconfig

@@ -7,7 +7,7 @@ indent_size = 2
 [{version-rules.xml,maven-wrapper.properties,checkstyle.xml,docker-compose.yaml,docker-compose.yml,Dockerfile,example_target_info.json,mise.toml,mvnm,mvnw.cmd,generate-protobuf.sh,.gitleaksignore,prometheus.properties}]
 max_line_length = 200
 
-[{grafana-dashboard-*.json,.editorconfig,super-linter.env,renovate.json5}]
+[{grafana-dashboard-*.json,.editorconfig,super-linter.env,lychee.toml,renovate.json5}]
 max_line_length = 300
 
 [pom.xml]
@@ -18,5 +18,5 @@ max_line_length = 120
 indent_size = 4
 max_line_length = 120
 
-[{.mise/tasks/build-release.sh,.mise/tasks/lint/super-linter.sh,.mise/tasks/lint/links-in-modified-files.sh,.github/workflows/multi-version-test.yml,.github/workflows/lint-rest.yml}]
+[{.mise/tasks/build-release.sh,.github/workflows/multi-version-test.yml}]
 max_line_length = 200