Bug: fetchIssueIDs discards GraphQL error — callers receive static "failed to get issue ID" with no root cause #2067

Bug Description

fetchIssueIDs in pkg/github/issues.go discards the underlying GraphQL error at both call sites (lines 65 and 87), returning only a static string with zero diagnostic context.

Affected Code

File: pkg/github/issues.go, lines 64-66 and 86-88

// Line 64-66
if err := gqlClient.Query(ctx, &query, vars); err != nil {
    return "", "", fmt.Errorf("failed to get issue ID")  // err is dropped
}

// Line 86-88
if err := gqlClient.Query(ctx, &query, vars); err != nil {
    return "", "", fmt.Errorf("failed to get issue ID")  // err is dropped
}

Both use fmt.Errorf("failed to get issue ID") with no %w verb and no reference to the captured err.

Impact

When CloseIssue (line ~1308) calls fetchIssueIDs and it fails, the caller's error message — "Failed to find issues" — cannot be supplemented with the actual root cause. Possible root causes that are silently swallowed:

• Authentication failure (expired token, insufficient scopes)
• Rate limiting (GraphQL secondary rate limits)
• Network error (DNS, timeout, TLS)
• Issue not found (wrong owner/repo, deleted issue)

All of these produce the same opaque error: failed to get issue ID.

Steps to Reproduce

1. Call CloseIssue with a valid owner/repo but an issue number that doesn't exist
2. Or trigger a GraphQL rate limit
3. Observe the error message contains no diagnostic information about why the query failed

Expected Behavior

Error should wrap the original cause:

return "", "", fmt.Errorf("failed to get issue ID: %w", err)

Actual Behavior

Error is a static string with no root cause context.

Proposed Solution

Option A (recommended): Wrap the error with %w

// Both call sites:
if err := gqlClient.Query(ctx, &query, vars); err != nil {
    return "", "", fmt.Errorf("failed to get issue ID: %w", err)
}

Option B: Use the project's ghErrors package for consistency with REST error handling patterns used elsewhere in the codebase.

Happy to submit a PR for this fix.