catalog: add golang func call in defer example

[Copilot]

This PR adds a Golang example to the catalog to detect a common anti-pattern where defer statements contain function calls with parameters that are evaluated immediately instead of when the defer executes.

The issue commonly occurs in Go testing code when using assertion libraries with failpoint management:

// ❌ Problematic - failpoint.Disable() is called immediately
defer require.NoError(t, failpoint.Disable("some/path"))

// ✅ Correct - wrapped in anonymous function
defer func() {
    require.NoError(t, failpoint.Disable("some/path"))
}()

In the problematic version, failpoint.Disable("some/path") is evaluated when the defer statement is encountered, not when the function exits. This makes the failpoint disabled immediately after being enabled, rendering tests ineffective.

Changes:

• Added website/catalog/go/defer-func-call-antipattern.md with:
  • Playground link using the pattern defer $A.$B(t, failpoint.$M($$$))
  • Clear explanation of the defer evaluation timing issue
  • YAML rule configuration with defer_statement selector
  • Real example from TiDB codebase showing the antipattern
  • Fix suggestion using anonymous functions
• Updated website/catalog/go/index.md to include the new example

The ast-grep pattern detects defer statements matching:

rule:
  pattern: |
    defer $A.$B(t, failpoint.$M($$$))
  selector: defer_statement

This addresses a real issue found in the TiDB codebase where thousands of similar problematic defer statements existed.

Fixes #793.

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[HerringtonDarkholme]

@copilot please remove npm-lock file since this repo is using pnpm

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[Copilot]

Pull Request Overview

This PR adds a new Go example to the ast-grep catalog that detects a common anti-pattern in defer statements where function calls are evaluated immediately instead of when the defer executes. The example specifically targets testing code that incorrectly defers assertion calls with failpoint management functions.

• Adds detection for defer statements that call assertion functions with failpoint methods as parameters
• Provides clear explanation of Go's defer evaluation timing and why this pattern is problematic
• Includes a real-world example from TiDB codebase and suggested fix using anonymous functions

Reviewed Changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 1 comment.

File	Description
website/catalog/go/defer-func-call-antipattern.md	New catalog entry with ast-grep rule to detect problematic defer statements in Go testing code
website/catalog/go/index.md	Added include directive for the new defer antipattern example

[Copilot]

@copilot please remove npm-lock file since this repo is using pnpm

Removed package-lock.json and updated .gitignore to prevent it from being added in the future since this repository uses pnpm. (commit c4f8e92)