refactor(t-paliad-092): rename Go module path patholo → paliad

F-6 from t-paliad-074 architecture audit. The Gitea repo was renamed
m/patholo → mAi/paliad → m/paliad, but go.mod still declared
`mgit.msbls.de/m/patholo` and every internal import echoed the
pre-rebrand name.

Sweep:
- go.mod: module path → mgit.msbls.de/m/paliad
- All *.go files: imports rewritten via sed
- README.md, docs/design-kanzlai-integration.md: mAi/paliad → m/paliad
- Frontend issue-reference comments (mAi/paliad#N → m/paliad#N) in
  i18n.ts, theme.ts, sidebar.ts, app.ts, Sidebar.tsx, PWAHead.tsx,
  global.css

Verified: go build/vet/test ./... clean, bun run build clean,
no remaining mgit.msbls.de/m/patholo or mAi/paliad references
outside docs that intentionally describe the rename history.

cmd/server/main.go

@@ -15,11 +15,11 @@ import (
 	// user's chosen tz (t-paliad-064 root cause). Adds ~450KB to the binary.
 	_ "time/tzdata"
 
-	"mgit.msbls.de/m/patholo/internal/auth"
-	"mgit.msbls.de/m/patholo/internal/branding"
-	"mgit.msbls.de/m/patholo/internal/db"
-	"mgit.msbls.de/m/patholo/internal/handlers"
-	"mgit.msbls.de/m/patholo/internal/services"
+	"mgit.msbls.de/m/paliad/internal/auth"
+	"mgit.msbls.de/m/paliad/internal/branding"
+	"mgit.msbls.de/m/paliad/internal/db"
+	"mgit.msbls.de/m/paliad/internal/handlers"
+	"mgit.msbls.de/m/paliad/internal/services"
 )
 
 func main() {