fix: include review context when custom fix instructions are provided (#395)

## Summary
- When a user provides custom instructions via Shift+F in the TUI fix
modal, the custom prompt was completely replacing the review context
instead of being appended to it
- The fix agent received only the user's short instructions with no
knowledge of what the review actually found, causing it to search
aimlessly and eventually give up
- Custom instructions are now combined with the review findings via
`buildFixPromptWithInstructions`, so the agent sees both the original
review output and the user's additional guidance

Closes #387

## Test plan
- [x] New test: `"custom prompt includes review context"` verifies
stored prompt contains both review output and custom instructions
- [x] All 3521 existing tests pass
- [ ] Manual: Shift+F on a review, enter custom instructions, verify
agent log shows review findings in the prompt

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: mariusvniekerk

internal/daemon/server.go

@@ -1901,8 +1901,8 @@ func (s *Server) handleFixJob(w http.ResponseWriter, r *http.Request) {
 	}
 
 	// Build the fix prompt
-	fixPrompt := req.Prompt
-	if fixPrompt == "" && req.StaleJobID > 0 {
+	fixPrompt := ""
+	if req.StaleJobID > 0 {
 		// Server-side rebase: look up stale patch from DB and build rebase prompt
 		staleJob, err := s.db.GetJobByID(req.StaleJobID)
 		if err != nil {
@@ -1943,7 +1943,11 @@ func (s *Server) handleFixJob(w http.ResponseWriter, r *http.Request) {
 			writeError(w, http.StatusBadRequest, "parent job has no review to fix")
 			return
 		}
-		fixPrompt = buildFixPrompt(review.Output)
+		if req.Prompt != "" {
+			fixPrompt = buildFixPromptWithInstructions(review.Output, req.Prompt)
+		} else {
+			fixPrompt = buildFixPrompt(review.Output)
+		}
 	}
 
 	// Resolve agent for fix workflow
@@ -2154,18 +2158,29 @@ func (s *Server) handleActivity(w http.ResponseWriter, r *http.Request) {
 
 // buildFixPrompt constructs a prompt for fixing review findings.
 func buildFixPrompt(reviewOutput string) string {
-	return "# Fix Request\n\n" +
+	return buildFixPromptWithInstructions(reviewOutput, "")
+}
+
+// buildFixPromptWithInstructions constructs a fix prompt that includes the review
+// findings and optional user-provided instructions.
+func buildFixPromptWithInstructions(reviewOutput, userInstructions string) string {
+	prompt := "# Fix Request\n\n" +
 		"An analysis was performed and produced the following findings:\n\n" +
 		"## Analysis Findings\n\n" +
-		reviewOutput +
-		"\n\n## Instructions\n\n" +
+		reviewOutput + "\n\n"
+	if userInstructions != "" {
+		prompt += "## Additional Instructions\n\n" +
+			userInstructions + "\n\n"
+	}
+	prompt += "## Instructions\n\n" +
 		"Please apply the suggested changes from the analysis above. " +
 		"Make the necessary edits to address each finding. " +
 		"Focus on the highest priority items first.\n\n" +
 		"After making changes:\n" +
 		"1. Verify the code still compiles/passes linting\n" +
 		"2. Run any relevant tests to ensure nothing is broken\n" +
 		"3. Stage the changes with git add but do NOT commit — the changes will be captured as a patch\n"
+	return prompt
 }
 
 // buildRebasePrompt constructs a prompt for re-applying a stale patch to current HEAD.

internal/daemon/server_ops_test.go

@@ -505,6 +505,47 @@ func TestHandleFixJobStaleValidation(t *testing.T) {
 		}
 	})
 
+	t.Run("custom prompt includes review context", func(t *testing.T) {
+		req := testutil.MakeJSONRequest(
+			t, http.MethodPost, "/api/job/fix",
+			fixJobRequest{
+				ParentJobID: reviewJob.ID,
+				Prompt:      "Ignore the security concern, it's only a testing binary.",
+			},
+		)
+		w := httptest.NewRecorder()
+		server.handleFixJob(w, req)
+
+		if w.Code != http.StatusCreated {
+			t.Fatalf(
+				"Expected 201 for fix enqueue with custom prompt, got %d: %s",
+				w.Code, w.Body.String(),
+			)
+		}
+
+		var fixJob storage.ReviewJob
+		testutil.DecodeJSON(t, w, &fixJob)
+
+		stored, err := db.GetJobByID(fixJob.ID)
+		if err != nil {
+			t.Fatalf("GetJobByID(%d): %v", fixJob.ID, err)
+		}
+
+		// The stored prompt must contain both the review output AND the custom instructions
+		if !strings.Contains(stored.Prompt, "FAIL: issues found") {
+			t.Fatalf(
+				"Expected fix prompt to contain review output, got:\n%s",
+				stored.Prompt,
+			)
+		}
+		if !strings.Contains(stored.Prompt, "Ignore the security concern") {
+			t.Fatalf(
+				"Expected fix prompt to contain custom instructions, got:\n%s",
+				stored.Prompt,
+			)
+		}
+	})
+
 	t.Run("fix job as parent is rejected", func(t *testing.T) {
 		// Create a fix job and try to use it as a parent
 		fixJob, _ := db.EnqueueJob(storage.EnqueueOpts{