feat: implement AI-assisted rename prompting feature

- Added data model for AI-assisted renaming including structures for prompts, responses, and policies.
- Created implementation plan detailing the integration of Google Genkit into the CLI for renaming tasks.
- Developed quickstart guide for setting up and using the new AI rename functionality.
- Documented research decisions regarding Genkit orchestration and prompt composition.
- Established tasks for phased implementation, including setup, foundational work, and user stories.
- Implemented contract tests to ensure AI rename policies and ledger metadata are correctly applied.
- Developed integration tests for validating AI rename flows, including preview, apply, and undo functionalities.
- Added tooling to pin Genkit dependency for consistent builds.

internal/output/table.go

@@ -46,3 +46,53 @@ func (f *tableFormatter) WriteSummary(w io.Writer, summary Summary) error {
 	_, err := fmt.Fprintln(w, DefaultSummaryLine(summary))
 	return err
 }
+
+// AIPlanRow represents a single AI plan preview row.
+type AIPlanRow struct {
+	Sequence  string
+	Original  string
+	Proposed  string
+	Sanitized string
+}
+
+// AIPlanTable renders AI plan previews in a tabular format.
+type AIPlanTable struct {
+	writer *tabwriter.Writer
+}
+
+// NewAIPlanTable constructs a table for AI plan previews.
+func NewAIPlanTable() *AIPlanTable {
+	return &AIPlanTable{}
+}
+
+// Begin writes the header for the AI plan table.
+func (t *AIPlanTable) Begin(w io.Writer) error {
+	if t.writer != nil {
+		return fmt.Errorf("ai plan table already initialized")
+	}
+	t.writer = tabwriter.NewWriter(w, 0, 4, 2, ' ', 0)
+	_, err := fmt.Fprintln(t.writer, "SEQ\tORIGINAL\tPROPOSED\tSANITIZED")
+	return err
+}
+
+// WriteRow appends a plan row to the table.
+func (t *AIPlanTable) WriteRow(row AIPlanRow) error {
+	if t.writer == nil {
+		return fmt.Errorf("ai plan table not initialized")
+	}
+	_, err := fmt.Fprintf(t.writer, "%s\t%s\t%s\t%s\n", row.Sequence, row.Original, row.Proposed, row.Sanitized)
+	return err
+}
+
+// End flushes the table to the underlying writer.
+func (t *AIPlanTable) End(w io.Writer) error {
+	if t.writer == nil {
+		return fmt.Errorf("ai plan table not initialized")
+	}
+	if err := t.writer.Flush(); err != nil {
+		return err
+	}
+	_, err := fmt.Fprintln(w)
+	t.writer = nil
+	return err
+}