fix(sql): throw on missing filepath in EnhancedCookieQueryService

[mherod]

Problem

EnhancedCookieQueryService.queryCookies() silently returned { data: [] } when no filepath was provided, because discoverBrowserFiles() was an unimplemented stub that unconditionally returned []. Callers had no way to distinguish "no cookies matched" from "file discovery is broken".

Solution

Replace the stub with a thrown Error that clearly names the browser and directs callers to provide an explicit filepath in EnhancedQueryOptions.

Changes

• src/core/browsers/sql/EnhancedCookieQueryService.ts: Remove the TODO stub and return [] from discoverBrowserFiles(). Throw a descriptive Error instead.
• src/core/browsers/sql/__tests__/EnhancedCookieQueryService.test.ts: New test file with 5 tests covering the error path (firefox, chrome, edge without filepath) and the happy path (with filepath provided).

Verification

• queryCookies({ browser: "firefox", name: "%", domain: "%" }) without filepath throws with message matching /Auto-discovery.*not yet implemented/
• TODO comment removed — confirmed via grep
• Unit tests added and passing (5/5)
• No regressions — 538 tests pass, 0 failures

Fixes #428

[claude]

PR Review: throw on missing filepath in EnhancedCookieQueryService

Overview

Replaces a silent stub (return []) with a descriptive thrown error, converting an invisible failure into an explicit contract violation. Clean, targeted fix for #428.

Findings

No critical or warning-level issues found.

🔵 Suggestions

• The three error-path tests check slightly different fragments of the same single error message (/Auto-discovery.*not yet implemented/, /"chrome"/, /filepath/). Collapsing them into one test with all three assertions would reduce duplication — though the current form is fine and readable.

👍 What's Good

• The fix is minimal: 6 lines removed, 4 added, exactly addresses the root cause
• getFilepaths call chain is clearly documented — the throw will surface correctly to all callers
• Tests cover both the error path (3 browsers) and the happy path (with filepath provided), confirming no regression
• Error message is actionable: tells the caller what to do (Provide an explicit "filepath"), not just what went wrong

Summary

LGTM. The change is correct, well-tested, and strictly better than a silent empty result. Ready to merge.