feat(domain): add commit message and project config models

- Define interfaces for commit messages, groups, and plans
- Implement parseTrailerText to parse commit trailers
- Add ProjectConfig and ProjectScope to represent project settings
- Provide emptyProjectConfig factory for default configuration
- Create renderCommitBody to format commit message body

This introduces domain entities for commit message handling and project
configurations. It includes parsing logic for trailers in commit
messages and utility functions for formatting. These additions serve as
foundational models for managing commits and project settings.

Co-Authored-By: Git Agent <noreply@git-agent.dev>

Author: xesrevinu

src/domain/commit.ts

@@ -0,0 +1,62 @@
+export interface Trailer {
+  readonly key: string;
+  readonly value: string;
+}
+
+export const parseTrailerText = (input: string): Trailer | undefined => {
+  const separator = ": ";
+  const index = input.indexOf(separator);
+  if (index <= 0) {
+    return undefined;
+  }
+
+  const key = input.slice(0, index).trim();
+  const value = input.slice(index + separator.length).trim();
+  if (key.length === 0 || value.length === 0) {
+    return undefined;
+  }
+
+  return {
+    key,
+    value,
+  };
+};
+
+export interface CommitMessage {
+  readonly title: string;
+  readonly bullets: ReadonlyArray<string>;
+  readonly explanation: string;
+}
+
+export interface CommitGroup {
+  readonly files: ReadonlyArray<string>;
+  readonly message: CommitMessage | undefined;
+}
+
+export interface CommitPlan {
+  readonly groups: ReadonlyArray<CommitGroup>;
+}
+
+export interface SingleCommitResult {
+  readonly title: string;
+  readonly explanation: string;
+  readonly files: ReadonlyArray<string>;
+  readonly output: string | undefined;
+}
+
+export const renderCommitBody = (message: CommitMessage): string => {
+  const bulletSection = message.bullets.map((bullet) => `- ${bullet}`).join("\n");
+  if (bulletSection.length === 0 && message.explanation.length === 0) {
+    return "";
+  }
+
+  if (bulletSection.length === 0) {
+    return message.explanation;
+  }
+
+  if (message.explanation.length === 0) {
+    return bulletSection;
+  }
+
+  return `${bulletSection}\n\n${message.explanation}`;
+};

src/domain/project.ts

@@ -0,0 +1,20 @@
+export interface ProjectScope {
+  readonly name: string;
+  readonly description?: string;
+}
+
+export interface ProjectConfig {
+  readonly scopes: ReadonlyArray<ProjectScope>;
+  readonly hooks: ReadonlyArray<string>;
+  readonly maxDiffLines: number;
+  readonly noGitAgentCoAuthor: boolean;
+  readonly noModelCoAuthor: boolean;
+}
+
+export const emptyProjectConfig = (): ProjectConfig => ({
+  scopes: [],
+  hooks: [],
+  maxDiffLines: 0,
+  noGitAgentCoAuthor: false,
+  noModelCoAuthor: false,
+});

tests/commit-inputs.test.ts

@@ -0,0 +1,26 @@
+import { describe, expect, it } from "vitest";
+import { parseTrailerText } from "../src/domain/commit";
+import { parseCsvValues } from "../src/shared/text";
+
+describe("repeatable commit inputs", () => {
+  it("flattens repeated and comma-separated values", () => {
+    expect(parseCsvValues(["alice", "bob, carol", "dave"])).toEqual([
+      "alice",
+      "bob",
+      "carol",
+      "dave",
+    ]);
+  });
+
+  it("parses a valid trailer value", () => {
+    expect(parseTrailerText("Reviewed-by: Ada Lovelace")).toEqual({
+      key: "Reviewed-by",
+      value: "Ada Lovelace",
+    });
+  });
+
+  it("rejects trailer values without the required separator", () => {
+    expect(parseTrailerText("Reviewed-by:Ada")).toBeUndefined();
+    expect(parseTrailerText("Reviewed-by")).toBeUndefined();
+  });
+});