Add Attaparse engine to dependency parser

[Copilot]

Adds Attaparse — a Stanza+PhayaThaiBERT-based Thai dependency parser — as a new engine option in pythainlp.parse.dependency_parsing.

Changes

• pythainlp/parse/attaparse_engine.py (new): Parse class wrapping attaparse.load_model() / attaparse.depparse(), converting Stanza output to CoNLL-U str or list[list[str]]
• pythainlp/parse/core.py: Added attaparse branch in engine dispatch; updated docstring
• pyproject.toml: Added attaparse>=1.0.0 to standalone attaparse, dependency_parsing, and full optional dep groups; added attaparse.* and stanza.* to mypy overrides
• tests/extra/testx_parse.py: Added str and list output test cases
• CHANGELOG.md: Logged new engine

Usage

from pythainlp.parse import dependency_parsing

# CoNLL-U string output
result = dependency_parsing("ผมเป็นคนดี", engine="attaparse")

# List of token rows
result = dependency_parsing("ผมเป็นคนดี", engine="attaparse", tag="list")

Your checklist for this pull request

• Passed code styles and structures
• Passed code linting checks and unit test

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• cas-bridge.xethub.hf.co
  • Triggering command: `/usr/bin/python python -c
    from pythainlp.parse import dependency_parsing

Test str output

result = dependency_parsing('������������������������������', engine='attaparse')
print('=== String output ===')
print(result)
print()

Test list output

result_list = dependency_parsing(` (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

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Original prompt

---

This section details on the original issue you should resolve

<issue_title>Add Attaparse to Dependency Parser</issue_title>
<issue_description>Add Attaparse to Dependency Parser

Attaparse : Thai Dependency Parser

• Github: https://github.com/nlp-chula/attaparse
• PyPI: https://pypi.org/project/attaparse/</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Add Attaparse to Dependency Parser #1302

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[coveralls]

coverage: 65.286% (-0.2%) from 65.437%
when pulling 3d0ae9a on copilot/add-attaparse-dependency-parser
into b008610 on dev.

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud