feat(twitter_threads): scaffold package + error types + typed dataclasses

TIER-2 READ AGENTS.md, conductor/workflow.md, conductor/edit_workflow.md, conductor/tier2/githooks/forbidden-files.txt, conductor/tracks/tier2_leak_prevention_20260620/spec.md (archived -> read docs/reports/2026-06-15/TRACK_COMPLETION_tier2_leak_prevention_20260620.md), conductor/code_styleguides/data_oriented_design.md, conductor/code_styleguides/python.md, conductor/code_styleguides/type_aliases.md, conductor/code_styleguides/error_handling.md, conductor/product-guidelines.md (Core Value via aggregate_directives) before Phase 1 (scaffold + error_types + dataclasses).

scripts/twitter_threads/__init__.py (namespace docstring); error_types.py (ErrorInfo + make_error + PostMetrics/PostData/ThreadData, frozen+slots); tests/test_twitter_threads_types.py (9 contract tests).

scripts/twitter_threads/__init__.py

@@ -0,0 +1,15 @@
+"""Twitter/X thread extraction reusable tooling.
+
+Standalone scripts that acquire posts, threads, and media from X (Twitter)
+and emit self-contained Markdown documents.
+
+Scripts in this namespace:
+- fetch_thread.py: acquire a post/thread (gallery-dl subprocess for URLs; html.parser for local HTML)
+- download_media.py: download referenced media via stdlib urllib
+- render_markdown.py: emit the Markdown document + media links
+- error_types.py: shared Result-style ErrorInfo + the ThreadData/PostData/PostMetrics dataclasses
+
+Standalone: no imports from src/ or conductor/; copy-pasteable to another repo with only gallery-dl as an external dep.
+
+Per conductor/code_styleguides/python.md, 1-space indent + type hints + no comments in implementation code.
+"""

scripts/twitter_threads/error_types.py

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+"""Shared dataclasses for the scripts.twitter_threads namespace."""
+from __future__ import annotations
+from dataclasses import dataclass
+
+@dataclass(frozen=True, slots=True)
+class ErrorInfo:
+ kind: str
+ source: str
+ detail: str
+
+def make_error(kind: str, source: str, detail: str) -> ErrorInfo:
+ return ErrorInfo(kind=kind, source=source, detail=detail)
+
+@dataclass(frozen=True, slots=True)
+class PostMetrics:
+ reply_count: int
+ repost_count: int
+ like_count: int
+ view_count: int | None
+
+@dataclass(frozen=True, slots=True)
+class PostData:
+ post_id: str
+ author: str
+ handle: str
+ text: str
+ timestamp: str
+ media_urls: tuple[str, ...]
+ reply_to_id: str | None
+ quote_of_id: str | None
+ metrics: PostMetrics
+
+@dataclass(frozen=True, slots=True)
+class ThreadData:
+ root_post_id: str
+ posts: tuple[PostData, ...]
+ source_url: str