[chore] upgrade golangci-lint to v2.1.6 and migrate config (#4265)

Signed-off-by: nicole mikołajczyk <git@mkljczk.pl>

# Description

Contribution guidelines link to the golangci-lint documentation for the up-to-date version rather than [the legacy v1 doc](https://golangci.github.io/legacy-v1-doc/), which uses a different configuration schema. I migrated the config using the `golangci-lint migrate` command, moved the comments, adjusted staticcheck config and ensured the rules still work.

## Checklist

- [x] I/we have read the [GoToSocial contribution guidelines](https://codeberg.org/superseriousbusiness/gotosocial/src/branch/main/CONTRIBUTING.md).
- [ ] I/we have discussed the proposed changes already, either in an issue on the repository, or in the Matrix chat.
- [x] I/we have not leveraged AI to create the proposed changes.
- [ ] I/we have performed a self-review of added code.
- [x] I/we have written code that is legible and maintainable by others.
- [ ] I/we have commented the added code, particularly in hard-to-understand areas.
- [ ] I/we have made any necessary changes to documentation.
- [ ] I/we have added tests that cover new code.
- [ ] I/we have run tests and they pass locally with the changes.
- [ ] I/we have run `go fmt ./...` and `golangci-lint run`.

Reviewed-on: https://codeberg.org/superseriousbusiness/gotosocial/pulls/4265
Co-authored-by: nicole mikołajczyk <git@mkljczk.pl>
Co-committed-by: nicole mikołajczyk <git@mkljczk.pl>

.golangci.yml

@@ -4,25 +4,21 @@
 #
 # For GoToSocial we mostly take the default linters, but we add a few to catch style issues as well.
 
+version: "2"
 # options for analysis running
 run:
   # include test files or not, default is true
   tests: false
-  # timeout for analysis, e.g. 30s, 5m, default is 1m
-  timeout: 5m
-
 linters:
   # enable some extra linters, see here for the list: https://golangci-lint.run/usage/linters/
   enable:
     - gocritic
-    - gofmt
     - goheader
     - gosec
     - nilerr
     - revive
-
   # https://golangci-lint.run/usage/linters/#linters-configuration
-linters-settings:
+  settings:
     # https://golangci-lint.run/usage/linters/#goheader
     goheader:
       template: |-
@@ -75,20 +71,25 @@ linters-settings:
         - name: unreachable-code
         # Disable below rules.
         - name: redefines-builtin-id
-        disabled: true # This one is just annoying.
+          disabled: true
         - name: unused-parameter
-        disabled: true # We often pass parameters to fulfil interfaces.
+          disabled: true
     # https://golangci-lint.run/usage/linters/#staticcheck
     staticcheck:
       # Enable all checks, but disable SA1012: nil context passing.
       # See: https://staticcheck.io/docs/configuration/options/#checks
-    checks: ["all", "-SA1012"]
-
-issues:
-  exclude-rules:
-    # Exclude VSCode custom folding region comments in files that use them.
-    # Already fixed in go-critic and can be removed next time go-critic is updated.
-    - linters:
-        - gocritic
-      path: internal/db/filter.go
-      text: 'commentFormatting: put a space between `//` and comment text'
+      checks:
+        - SA*
+        - -SA1012
+  exclusions:
+    generated: lax
+    presets:
+      - comments
+      - common-false-positives
+      - legacy
+      - std-error-handling
+formatters:
+  enable:
+    - gofmt
+  exclusions:
+    generated: lax

.woodpecker/pr.yaml

@@ -22,7 +22,7 @@ steps:
 
     # We use golangci-lint for linting.
     # See: https://golangci-lint.run/
-    image: golangci/golangci-lint:v1.64.8
+    image: golangci/golangci-lint:v2.1.6
     pull: true
 
     # https://woodpecker-ci.org/docs/administration/configuration/backends/docker#run-user