refactor(pr-patrol): decompose monolith, fix bugs, expand test coverage

- Split 1,560-line index.ts into 8 focused modules:
  types.ts, state.ts, detection.ts, scoring.ts, merge.ts,
  prompts.ts, execution.ts, reflection.ts
- Add pr-patrol/**/*.test.ts to vitest config (tests were silently ignored)
- Fix empty catch blocks violating error-handling rules
- Add missing stale PR section in buildPrompt()
- Fix summary comment mid-line truncation (take last ~500 chars by line)
- Fix overlap comment replace() to use replaceAll()
- Add staleHours CLI option (was env-var only)
- Move state persistence from /tmp to ~/.cache/pr-patrol/state/
  with backward-compatible migration from legacy location
- Parallelize overlap detection file fetches (Promise.allSettled)
- Include PR #1826 budget/timeout improvements in the decomposed modules
- Add 46 new tests (scoring, prompts, detection) → 74 total

Closes #1830
Closes #1831

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: OAGr

crux/commands/pr-patrol.ts

@@ -197,6 +197,7 @@ Daemon Options:
   --max-turns=N     Max Claude turns per fix (default: 40)
   --timeout=N       Hard timeout in minutes per fix (default: 30)
   --cooldown=N      Skip recently-processed PRs for N seconds (default: 1800)
+  --stale-hours=N   Hours before a PR is considered stale (default: 48)
   --model=MODEL     Claude model (default: sonnet)
   --skip-perms      Add --dangerously-skip-permissions to Claude CLI
   --verbose         Detailed output

crux/pr-patrol/detection.test.ts

@@ -0,0 +1,240 @@
+import { describe, it, expect } from 'vitest';
+import { detectIssues, extractBotComments } from './detection.ts';
+import type { GqlPrNode } from './types.ts';
+
+function makePrNode(overrides: Partial<GqlPrNode> = {}): GqlPrNode {
+  return {
+    number: 1,
+    title: 'Test PR',
+    headRefName: 'claude/test',
+    mergeable: 'MERGEABLE',
+    isDraft: false,
+    createdAt: '2026-01-01T00:00:00Z',
+    updatedAt: '2026-03-05T00:00:00Z',
+    body: '## Summary\n\n- [x] Task done\n\n## Test plan\n\n- [x] Tests pass\n\nCloses #1',
+    labels: { nodes: [{ name: 'ready-to-merge' }] },
+    commits: {
+      nodes: [
+        {
+          commit: {
+            statusCheckRollup: {
+              contexts: {
+                nodes: [{ conclusion: 'SUCCESS' }],
+              },
+            },
+          },
+        },
+      ],
+    },
+    reviewThreads: { nodes: [] },
+    ...overrides,
+  };
+}
+
+// ── extractBotComments ───────────────────────────────────────────────────────
+
+describe('extractBotComments', () => {
+  it('extracts unresolved bot comments', () => {
+    const pr = makePrNode({
+      reviewThreads: {
+        nodes: [{
+          isResolved: false,
+          isOutdated: false,
+          path: 'src/foo.ts',
+          line: 10,
+          startLine: null,
+          comments: {
+            nodes: [{ author: { login: 'coderabbitai' }, body: '🟠 Major: Fix this' }],
+          },
+        }],
+      },
+    });
+    const comments = extractBotComments(pr);
+    expect(comments).toHaveLength(1);
+    expect(comments[0].path).toBe('src/foo.ts');
+    expect(comments[0].author).toBe('coderabbitai');
+  });
+
+  it('skips resolved threads', () => {
+    const pr = makePrNode({
+      reviewThreads: {
+        nodes: [{
+          isResolved: true,
+          isOutdated: false,
+          path: 'src/foo.ts',
+          line: 10,
+          startLine: null,
+          comments: {
+            nodes: [{ author: { login: 'coderabbitai' }, body: 'Fix this' }],
+          },
+        }],
+      },
+    });
+    expect(extractBotComments(pr)).toHaveLength(0);
+  });
+
+  it('skips outdated threads', () => {
+    const pr = makePrNode({
+      reviewThreads: {
+        nodes: [{
+          isResolved: false,
+          isOutdated: true,
+          path: 'src/foo.ts',
+          line: 10,
+          startLine: null,
+          comments: {
+            nodes: [{ author: { login: 'coderabbitai' }, body: 'Fix this' }],
+          },
+        }],
+      },
+    });
+    expect(extractBotComments(pr)).toHaveLength(0);
+  });
+
+  it('skips non-bot authors', () => {
+    const pr = makePrNode({
+      reviewThreads: {
+        nodes: [{
+          isResolved: false,
+          isOutdated: false,
+          path: 'src/foo.ts',
+          line: 10,
+          startLine: null,
+          comments: {
+            nodes: [{ author: { login: 'humanuser' }, body: 'Fix this' }],
+          },
+        }],
+      },
+    });
+    expect(extractBotComments(pr)).toHaveLength(0);
+  });
+
+  it('recognizes all known bot logins', () => {
+    const bots = ['coderabbitai', 'github-actions', 'dependabot', 'renovate'];
+    for (const bot of bots) {
+      const pr = makePrNode({
+        reviewThreads: {
+          nodes: [{
+            isResolved: false,
+            isOutdated: false,
+            path: 'src/test.ts',
+            line: 1,
+            startLine: null,
+            comments: {
+              nodes: [{ author: { login: bot }, body: 'Fix' }],
+            },
+          }],
+        },
+      });
+      expect(extractBotComments(pr)).toHaveLength(1);
+    }
+  });
+
+  it('returns empty for PR with no review threads', () => {
+    const pr = makePrNode({ reviewThreads: undefined });
+    expect(extractBotComments(pr)).toEqual([]);
+  });
+});
+
+// ── detectIssues ─────────────────────────────────────────────────────────────
+
+describe('detectIssues', () => {
+  it('detects bot-review-major for actionable severity', () => {
+    const pr = makePrNode({
+      reviewThreads: {
+        nodes: [{
+          isResolved: false,
+          isOutdated: false,
+          path: 'src/foo.ts',
+          line: 10,
+          startLine: null,
+          comments: {
+            nodes: [{ author: { login: 'coderabbitai' }, body: '🟠 Major: Important issue' }],
+          },
+        }],
+      },
+    });
+    const result = detectIssues(pr, 0);
+    expect(result.issues).toContain('bot-review-major');
+    expect(result.issues).not.toContain('bot-review-nitpick');
+  });
+
+  it('detects bot-review-nitpick for non-actionable severity', () => {
+    const pr = makePrNode({
+      reviewThreads: {
+        nodes: [{
+          isResolved: false,
+          isOutdated: false,
+          path: 'src/foo.ts',
+          line: 10,
+          startLine: null,
+          comments: {
+            nodes: [{ author: { login: 'coderabbitai' }, body: '🧹 Nitpick: Minor style' }],
+          },
+        }],
+      },
+    });
+    const result = detectIssues(pr, 0);
+    expect(result.issues).toContain('bot-review-nitpick');
+    expect(result.issues).not.toContain('bot-review-major');
+  });
+
+  it('detects stale PRs', () => {
+    const pr = makePrNode({
+      updatedAt: '2020-01-01T00:00:00Z',
+    });
+    const result = detectIssues(pr, Date.now());
+    expect(result.issues).toContain('stale');
+  });
+
+  it('does not flag recent PRs as stale', () => {
+    const pr = makePrNode({
+      updatedAt: new Date().toISOString(),
+    });
+    const result = detectIssues(pr, Date.now() - 1000);
+    expect(result.issues).not.toContain('stale');
+  });
+
+  it('handles null PR body gracefully', () => {
+    const pr = makePrNode({ body: null });
+    const result = detectIssues(pr, 0);
+    expect(result.issues).toContain('missing-testplan');
+    expect(result.issues).toContain('missing-issue-ref');
+  });
+
+  it('handles null statusCheckRollup', () => {
+    const pr = makePrNode({
+      commits: {
+        nodes: [{
+          commit: { statusCheckRollup: null },
+        }],
+      },
+    });
+    const result = detectIssues(pr, 0);
+    expect(result.issues).not.toContain('ci-failure');
+  });
+
+  it('detects ERROR state in StatusContext nodes', () => {
+    const pr = makePrNode({
+      commits: {
+        nodes: [{
+          commit: {
+            statusCheckRollup: {
+              contexts: { nodes: [{ state: 'ERROR' }] },
+            },
+          },
+        }],
+      },
+    });
+    const result = detectIssues(pr, 0);
+    expect(result.issues).toContain('ci-failure');
+  });
+
+  it('accepts Fixes and Resolves as issue refs', () => {
+    for (const keyword of ['Closes #1', 'Fixes #2', 'Resolves #3']) {
+      const pr = makePrNode({ body: `## Test plan\n\n${keyword}` });
+      const result = detectIssues(pr, 0);
+      expect(result.issues).not.toContain('missing-issue-ref');
+    }
+  });
+});