feat: add Response option & new custom headers

[dwisiswant0]

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Summary

Explains the information and/or motivation for making this changes...

Proposed of changes

This PR fixes/implements the following bugs/features:

• Bug 1
• Bug 2
• Feature 1
• Feature 2
• Breaking changes

How has this been tested?

Proof:

Closing issues

Fixes #

Checklist:

• [x] My code follows the code style of this project.
• [x] My changes successfully ran and pass linters locally (run make lint).
• [x] I have written new tests for my changes.
  • [x] My changes successfully ran and pass tests locally.
• [x] My change requires a change to the documentation.
  • [x] I have updated the documentation accordingly.

[dwisiswant0]

TODO:

• [x] Update Response interface usage.

[codecov-commenter]

Codecov Report

Patch coverage: 92.50% and project coverage change: +0.66% :tada:

Comparison is base (137a2e7) 71.78% compared to head (f531c61) 72.44%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #70 +/- ## ========================================== + Coverage 71.78% 72.44% +0.66% ========================================== Files 5 5 Lines 964 998 +34 ========================================== + Hits 692 723 +31 - Misses 227 229 +2 - Partials 45 46 +1 ``` | [Files Changed](https://app.codecov.io/gh/kitabisa/teler-waf/pull/70?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=kitabisa) | Coverage Δ | | |---|---|---| | [teler.go](https://app.codecov.io/gh/kitabisa/teler-waf/pull/70?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=kitabisa#diff-dGVsZXIuZ28=) | `67.24% <81.25%> (+0.49%)` | :arrow_up: | | [handler.go](https://app.codecov.io/gh/kitabisa/teler-waf/pull/70?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=kitabisa#diff-aGFuZGxlci5nbw==) | `88.23% <100.00%> (+4.90%)` | :arrow_up: | | [utils.go](https://app.codecov.io/gh/kitabisa/teler-waf/pull/70?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=kitabisa#diff-dXRpbHMuZ28=) | `87.59% <100.00%> (+0.39%)` | :arrow_up: |

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