Revert "feat(ecc): prune plugin 43→12 items, promote 7 rules to .claude/rules/ (#245)"

This reverts commit 1bd68ff534.

.opencode/commands/go-build.md

@@ -0,0 +1,87 @@
+---
+description: Fix Go build and vet errors
+agent: go-build-resolver
+subtask: true
+---
+
+# Go Build Command
+
+Fix Go build, vet, and compilation errors: $ARGUMENTS
+
+## Your Task
+
+1. **Run go build**: `go build ./...`
+2. **Run go vet**: `go vet ./...`
+3. **Fix errors** one by one
+4. **Verify fixes** don't introduce new errors
+
+## Common Go Errors
+
+### Import Errors
+```
+imported and not used: "package"
+```
+**Fix**: Remove unused import or use `_` prefix
+
+### Type Errors
+```
+cannot use x (type T) as type U
+```
+**Fix**: Add type conversion or fix type definition
+
+### Undefined Errors
+```
+undefined: identifier
+```
+**Fix**: Import package, define variable, or fix typo
+
+### Vet Errors
+```
+printf: call has arguments but no formatting directives
+```
+**Fix**: Add format directive or remove arguments
+
+## Fix Order
+
+1. **Import errors** - Fix or remove imports
+2. **Type definitions** - Ensure types exist
+3. **Function signatures** - Match parameters
+4. **Vet warnings** - Address static analysis
+
+## Build Commands
+
+```bash
+# Build all packages
+go build ./...
+
+# Build with race detector
+go build -race ./...
+
+# Build for specific OS/arch
+GOOS=linux GOARCH=amd64 go build ./...
+
+# Run go vet
+go vet ./...
+
+# Run staticcheck
+staticcheck ./...
+
+# Format code
+gofmt -w .
+
+# Tidy dependencies
+go mod tidy
+```
+
+## Verification
+
+After fixes:
+```bash
+go build ./...    # Should succeed
+go vet ./...      # Should have no warnings
+go test ./...     # Tests should pass
+```
+
+---
+
+**IMPORTANT**: Fix errors only. No refactoring, no improvements. Get the build green with minimal changes.