fix(KB-143): fix parseFileScopeFromPrompt regex and add tests

- Replace single-pass multiline regex with heading match + slice approach to avoid lazy quantifier issues
- Fix section extraction to correctly handle File Scope as both mid-file and last section
- Add tests for File Scope followed by another heading, at end of file, missing section, missing PROMPT.md, and glob patterns

packages/core/src/store.test.ts

@@ -757,6 +757,115 @@ describe("TaskStore", () => {
     });
   });
 
+  describe("parseFileScopeFromPrompt", () => {
+    it("returns paths when File Scope is followed by another heading", async () => {
+      const task = await store.createTask({ description: "Mid-file scope" });
+      const dir = join(rootDir, ".kb", "tasks", task.id);
+      await writeFile(
+        join(dir, "PROMPT.md"),
+        `# ${task.id}: Mid-file scope
+
+## File Scope
+
+- \`packages/core/src/store.ts\`
+- \`packages/core/src/store.test.ts\`
+
+## Steps
+
+### Step 0: Preflight
+- [ ] Check things
+`,
+      );
+
+      const paths = await store.parseFileScopeFromPrompt(task.id);
+      expect(paths).toEqual([
+        "packages/core/src/store.ts",
+        "packages/core/src/store.test.ts",
+      ]);
+    });
+
+    it("returns all paths when File Scope is the last section", async () => {
+      const task = await store.createTask({
+        description: "End-of-file scope",
+      });
+      const dir = join(rootDir, ".kb", "tasks", task.id);
+      await writeFile(
+        join(dir, "PROMPT.md"),
+        `# ${task.id}: End-of-file scope
+
+## Steps
+
+### Step 0: Preflight
+- [ ] Check things
+
+## File Scope
+
+- \`packages/core/src/store.ts\`
+- \`packages/core/src/store.test.ts\`
+- \`packages/core/src/utils.ts\`
+`,
+      );
+
+      const paths = await store.parseFileScopeFromPrompt(task.id);
+      expect(paths).toEqual([
+        "packages/core/src/store.ts",
+        "packages/core/src/store.test.ts",
+        "packages/core/src/utils.ts",
+      ]);
+    });
+
+    it("returns empty array when no File Scope section exists", async () => {
+      const task = await store.createTask({ description: "No scope" });
+      const dir = join(rootDir, ".kb", "tasks", task.id);
+      await writeFile(
+        join(dir, "PROMPT.md"),
+        `# ${task.id}: No scope
+
+## Steps
+
+### Step 0: Preflight
+- [ ] Check things
+`,
+      );
+
+      const paths = await store.parseFileScopeFromPrompt(task.id);
+      expect(paths).toEqual([]);
+    });
+
+    it("returns empty array when PROMPT.md does not exist", async () => {
+      const task = await store.createTask({ description: "No prompt" });
+      const dir = join(rootDir, ".kb", "tasks", task.id);
+      const { unlink } = await import("node:fs/promises");
+      await unlink(join(dir, "PROMPT.md"));
+
+      const paths = await store.parseFileScopeFromPrompt(task.id);
+      expect(paths).toEqual([]);
+    });
+
+    it("handles glob patterns in backtick-quoted paths", async () => {
+      const task = await store.createTask({ description: "Glob scope" });
+      const dir = join(rootDir, ".kb", "tasks", task.id);
+      await writeFile(
+        join(dir, "PROMPT.md"),
+        `# ${task.id}: Glob scope
+
+## File Scope
+
+- \`packages/core/*\`
+- \`packages/cli/src/commands/dashboard.ts\`
+- \`packages/engine/src/**/*.ts\`
+`,
+      );
+
+      const paths = await store.parseFileScopeFromPrompt(task.id);
+      expect(paths).toEqual([
+        "packages/core/*",
+        "packages/cli/src/commands/dashboard.ts",
+        "packages/engine/src/**/*.ts",
+      ]);
+    });
+  });
+
   describe("columnMovedAt", () => {
     it("createTask sets columnMovedAt", async () => {
       const before = new Date().toISOString();

packages/core/src/store.ts

@@ -500,13 +500,16 @@ export class TaskStore extends EventEmitter<TaskStoreEvents> {
 
     const content = await readFile(promptPath, "utf-8");
 
-    // Find the ## File Scope section
-    const fileScopeMatch = content.match(
-      /^##\s+File\s+Scope\s*\n([\s\S]*?)(?=\n##\s|\n#\s|$)/m,
-    );
-    if (!fileScopeMatch) return [];
+    // Find the ## File Scope section.
+    // We locate the heading then slice to the next heading (or end of file)
+    // to avoid multiline `$` anchor issues with lazy quantifiers.
+    const headingMatch = content.match(/^##\s+File\s+Scope\s*$/m);
+    if (!headingMatch) return [];
 
-    const section = fileScopeMatch[1];
+    const startIdx = headingMatch.index! + headingMatch[0].length;
+    const rest = content.slice(startIdx);
+    const nextHeading = rest.search(/\n##?\s/);
+    const section = nextHeading === -1 ? rest : rest.slice(0, nextHeading);
     const paths: string[] = [];
     const backtickRegex = /`([^`]+)`/g;
     let match;