fix(ipc): crash modal reads wrapper, search wired to real handler

CrashReportModal crashed on dumps.map because ipc.crash.read returns
{ ok, data } and the consumer was assigning the wrapper to state. Now
unwraps .data and falls back to [] on error.

ipc.file.search was miswired to ipc.file.pickFile — clicking 'Search'
popped a file picker instead of searching. Add real 'search-in-files'
handler in src/main/files/search-in-files.js with regex support,
case-sensitivity toggle, .git/node_modules/dist skip, 2MB file cap, and
1000-result limit. Wire preload bridge + TS declaration + allowlist.

Also:
- Drop dead ipc.file.open wrapper that was miswired to pickFile
- Rename FileEntry field 'modified' to 'modifiedAt' (number) so the
  IPC payload matches the declared type
- Update CrashReportModal tests to use the safeCall envelope shape

tests/unit/main/files/search-in-files.test.js

@@ -0,0 +1,87 @@
+const fs = require('fs');
+const path = require('path');
+const os = require('os');
+
+const { searchInFiles } = require('../../../../src/main/files/search-in-files');
+
+describe('searchInFiles', () => {
+  let tmpDir;
+
+  beforeEach(() => {
+    tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'search-in-files-'));
+  });
+  afterEach(() => {
+    fs.rmSync(tmpDir, { recursive: true, force: true });
+  });
+
+  test('returns empty array when rootPath or query missing', () => {
+    expect(searchInFiles({ rootPath: '', query: 'x' })).toEqual([]);
+    expect(searchInFiles({ rootPath: tmpDir, query: '' })).toEqual([]);
+  });
+
+  test('finds a literal substring in a single file', () => {
+    const f = path.join(tmpDir, 'a.md');
+    fs.writeFileSync(f, 'hello world\nsecond line\nhello again');
+    const out = searchInFiles({ rootPath: tmpDir, query: 'hello' });
+    expect(out).toEqual([
+      { filePath: f, line: 1, content: 'hello world' },
+      { filePath: f, line: 3, content: 'hello again' },
+    ]);
+  });
+
+  test('respects caseSensitive flag (default false)', () => {
+    const f = path.join(tmpDir, 'a.md');
+    fs.writeFileSync(f, 'Foo bar\nfoo BAR');
+    expect(searchInFiles({ rootPath: tmpDir, query: 'foo' }).length).toBe(2);
+    expect(searchInFiles({ rootPath: tmpDir, query: 'foo', caseSensitive: true }).length).toBe(1);
+  });
+
+  test('supports regex when isRegex is true', () => {
+    const f = path.join(tmpDir, 'a.md');
+    fs.writeFileSync(f, 'foo123\nbar\nbaz456');
+    const out = searchInFiles({ rootPath: tmpDir, query: '\\w+\\d+', isRegex: true });
+    expect(out.map((r) => r.content)).toEqual(['foo123', 'baz456']);
+  });
+
+  test('invalid regex returns empty array (does not throw)', () => {
+    expect(searchInFiles({ rootPath: tmpDir, query: '[unclosed', isRegex: true })).toEqual([]);
+  });
+
+  test('skips node_modules, .git, dist directories', () => {
+    const skip = path.join(tmpDir, 'node_modules');
+    fs.mkdirSync(skip);
+    fs.writeFileSync(path.join(skip, 'a.md'), 'match me');
+    const keep = path.join(tmpDir, 'src');
+    fs.mkdirSync(keep);
+    fs.writeFileSync(path.join(keep, 'b.md'), 'match me');
+    const out = searchInFiles({ rootPath: tmpDir, query: 'match' });
+    expect(out.length).toBe(1);
+    expect(out[0].filePath).toContain('src/b.md');
+  });
+
+  test('skips files larger than 2MB', () => {
+    const big = path.join(tmpDir, 'big.md');
+    fs.writeFileSync(big, 'a'.repeat(3 * 1024 * 1024));
+    expect(searchInFiles({ rootPath: tmpDir, query: 'a' })).toEqual([]);
+  });
+
+  test('recurses into subdirectories', () => {
+    const sub = path.join(tmpDir, 'a', 'b', 'c');
+    fs.mkdirSync(sub, { recursive: true });
+    const f = path.join(sub, 'deep.md');
+    fs.writeFileSync(f, 'needle here');
+    const out = searchInFiles({ rootPath: tmpDir, query: 'needle' });
+    expect(out.length).toBe(1);
+    expect(out[0].filePath).toBe(f);
+    expect(out[0].line).toBe(1);
+  });
+
+  test('caps results at 1000', () => {
+    const f = path.join(tmpDir, 'many.md');
+    const lines = [];
+    for (let i = 0; i < 1500; i++) lines.push('match line');
+    fs.writeFileSync(f, lines.join('\n'));
+    const out = searchInFiles({ rootPath: tmpDir, query: 'match' });
+    expect(out.length).toBe(1000);
+  });
+});