perf(rspack_core): replace `HASH_PLACEHOLDER_REGEX` with simple string parsing

[shulaoda]

Summary

Related to https://github.com/rolldown/rolldown/pull/1496 and https://github.com/oxc-project/oxc/issues/5586

I'm not sure if the hash pattern appears only once. If there are cases where the pattern appears multiple times, such as [hash]-[hash:6].js, I need to optimize further.

Checklist

• [ ] Tests updated (or not required).
• [ ] Documentation updated (or not required).

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[chenjiahan]

@shulaoda can you resolve the conflicts? ❤️

[h-a-n-a]

Wasn't the issue in the description had been resolved? I think this is necessary.

I'm not sure if the hash pattern appears only once. If there are cases where the pattern appears multiple times, such as [hash]-[hash:6].js, I need to optimize further.

let result = replace_all_hash_pattern("hello-[hash]-[hash:5].js", "[hash]", |n| {
    &"abcdefgh"[..n.unwrap_or(8)]
  });
 assert_eq!(result, Some("hello-abcdefgh-abcde.js".to_string()));

[shulaoda]

Wasn't the issue in the description had been resolved? I think this is necessary.

Sorry. This is a PR from a long time ago, and I fixed the issues in the description later. I have revised the description.