Golangcilint in build pipeline and fix lint errors

- Fix bad permissions bits for files
- VPNSP is 'private internet access' instead of 'pia' (retro compatible)
- Check errors of deferred unsetEnv functions in params package
-  Other lint errors fixing and code simplifications

.golangci.yml

@@ -0,0 +1,50 @@
+linters-settings:
+  maligned:
+    suggest-new: true
+  misspell:
+    locale: US
+
+linters:
+  disable-all: true
+  enable:
+    - bodyclose
+    - deadcode
+    - dogsled
+    - dupl
+    - errcheck
+    - gochecknoglobals
+    - gochecknoinits
+    - gocognit
+    - goconst
+    - gocritic
+    - gocyclo
+    - goimports
+    - golint
+    - gosec
+    - gosimple
+    - govet
+    - ineffassign
+    - interfacer
+    - maligned
+    - misspell
+    - nakedret
+    - prealloc
+    - rowserrcheck
+    - scopelint
+    - staticcheck
+    - structcheck
+    - typecheck
+    - unconvert
+    - unparam
+    - unused
+    - varcheck
+    - whitespace
+
+run:
+  skip-dirs:
+    - .devcontainer
+    - .github
+    - postgres
+
+service:
+  golangci-lint-version: 1.24.x # use the fixed version to not introduce new linters unexpectedly