feat: add persistent on-disk cache (#74)

* feat: add persistent on-file cache

* chore: pass filesystem to cache

* fix: reorder create mute callback data

* chore: fixed tests

* chore: add fs.WriteFile tests

* chore: add cache load/save tests

* chore: forgot to commit

feat: add silences count when creating silence via callback (#73)

feat: allow confirming silence and clearing the keyboard (#65)

chore: refactor keyboard pagination (#64)

* chore: refactor keyboard pagination

* chore: allow using pagination with custom page callback data

feat: refactor /alerts cmd and add 100% coverage (#62)

* feat: refactor /alerts cmd and add 100% coverage

* chore: updated config

feat: hide buttons after deleting; allow deleting after creating sile…

…nce (#41)

* feat: hide buttons after deleting; allow deleting after creating silence

* chore: bump golang version in CI

chore: fix goreleaser (#39)

feat: allow muting with custom comments (#37)

feat: add validate-config command (#36)

feat: add header auth (#35)

* feat: add header auth

* chore: fixed linting

* fix: use header auth first