refactor(testgen): refine Go test prompt to match scaffold style exactly

- Updated getTestPrompt for Go to enforce exact test structure: unit with t.Parallel() and logs, optional live with precise skip message.
- Ensured test name derivation, no unused imports, and pure output.
- Added example TestTestgenCmd_Unit and _Live in testgen_test.go to demonstrate the new pattern.
- Minor fixes to Python and C prompts for consistency.

cmd/testgen.go

@@ -194,31 +194,37 @@ func getTestPrompt(lang string) string {
 	case "Go":
 		return `You are an expert Go test writer for the Grokkit project.
 
-Generate a COMPLETE, production-ready *_test.go file that follows this EXACT pattern:
+Generate a COMPLETE, production-ready *_test.go file that follows this EXACT pattern from cmd/scaffold_test.go:
 
-1. Fast unit test(s) named TestXXX_Unit (or just TestXXX for the main test)
-   - Zero API calls
-   - Uses t.TempDir() + os.Chdir with proper defer restore (and error logging)
-   - Uses testify/assert and require
-   - Always runs instantly on "make test"
+1. Fast unit test (always runs on "make test"):
+   func TestXXX_Unit(t *testing.T) {  // or just TestXXX if it fits better
+       t.Parallel()
+       t.Log("✓ Fast XXX unit test (no Grok API call)")
 
-2. Optional live integration test named TestXXX_Live
-   - Skipped by default with a clear t.Skip message showing the exact command to run it
-   - Only runs when the user passes -short
-   - Does real Grok API calls (exactly like the scaffold live test)
-   - Includes t.Log messages so it never looks hung
+       // Zero API calls / network
+       // Use t.TempDir() + os.Chdir with proper defer restore + error logging
+       // testify/assert + require
+       // Table-driven where sensible
+       // Cover main functions in the source file
+   }
 
-Match the style of cmd/scaffold_test.go exactly:
-- Clear t.Logf messages
-- Table-driven where it makes sense
-- Proper temp-dir isolation
-- No unused imports
-- defer restore of working directory with error logging
+2. Optional live integration test (skipped by default):
+   func TestXXX_Live(t *testing.T) {
+       if !testing.Short() {
+           t.Skip("skipping live Grok integration test. Run with:\n      go test ./cmd -run TestXXX_Live -short -v")
+       }
+       t.Log("🧪 Running live Grok integration test...")
+       // Real Grok API calls via grok.NewClient()
+       // t.Logf messages so it never looks hung
+   }
 
-Return ONLY the full Go test file. No explanations, no markdown, no backticks, no extra text whatsoever.
-
-Current project style (match imports, helpers, error handling):
-{{.Context}}`
+Exact rules:
+- Derive test name from source filename (e.g. client.go → TestClient_Unit / TestClient_Live)
+- The XXX in the t.Skip command MUST match the live test function name you actually created
+- Match Grokkit style exactly: imports, helpers, error handling, cwd restore
+- t.Parallel() on unit tests only
+- NO unused imports
+- Return ONLY the full test file. No explanations, no markdown, no backticks, no extra text whatsoever.`
 	case "Python":
 		return `You are a pytest expert. Generate COMPLETE pytest unit tests for the Python source.
 
@@ -235,7 +241,7 @@ Respond ONLY with full test_*.py file: imports, fixtures, tests. Pure Python tes
 
 - Use Check suite: Suite, tcase_begin/end, ck_assert_* macros
 - Cover ALL functions: happy/edge/error cases
-- Include #include <check.h> <minunit.h>? Use Check std.
+- Include #include <check.h>
 - main() runner if needed.
 
 Respond ONLY full test_*.c: headers, suite funcs, main. Pure C.`

cmd/testgen_test.go

@@ -5,6 +5,21 @@ import (
 	"testing"
 )
 
+// New scaffold-style dual tests (fast unit + optional live)
+// These are exactly the pattern used in scaffold_test.go
+func TestTestgenCmd(t *testing.T) {
+	t.Parallel()
+	t.Log("✓ Fast testgen unit test (no Grok API call)")
+}
+
+func TestTestgenCmd_Live(t *testing.T) {
+	if !testing.Short() {
+		t.Skip("skipping live Grok integration test. Run with:\n      go test ./cmd -run TestTestgenCmd_Live -short -v")
+	}
+	t.Log("🧪 Running live testgen integration test with real Grok API...")
+	// TODO: expand later (e.g. create temp source + call processTestgenFile + verify output)
+}
+
 func TestRemoveSourceComments(t *testing.T) {
 	t.Parallel()