Restructure into reusable libraries + per-harness install extras

[krmayankb]

Motivation

SOCBench is organized around per-capability harnesses, but the repo isn't: the detection harness lives flat under src/socbench/, mixed with shared infrastructure. Users should pick their harness at install time:

uv pip install -e ".[dev,detection]"
uv pip install -e ".[dev,patchloop]"

Future harnesses (triage, hunting) land as sibling packages reusing the shared libraries.

Layout

Rule: top level of src/socbench/ = shared, harness-agnostic; subpackages = one harness each. Harnesses import from top level, never from each other.

src/socbench/
├── cli.py            # entry point, mounts harness commands (existing commands unchanged)
├── providers/        # shared: LLM adapters
├── pricing.py        # shared: extracted from config.py
├── hashing.py, logging_config.py
├── detection/        # agent, tools/, index, sampling, scoring, schema, prompts,
│                     #   aggregate, models, config, cli commands
└── patchloop/        # TS harness, untouched; Python side is a separate issue

agent.py and tools/ stay in detection/; extracting a harness-neutral loop waits for a second consumer.

Extras

• Base deps shrink to shared needs (pydantic, pyyaml, click, rich, jsonschema, python-json-logger).
• detection = polars, duckdb, pyarrow + provider SDKs (one-command runnable).
• patchloop = [] placeholder (harness is Node 20+, which pip can't express).
• Bare pip install socbench and socbench --help must still work.

Tasks

• Move detection modules to src/socbench/detection/; extract pricing.py
• Rewrite imports (all absolute, mechanical) in src + 16 test files
• pyproject: extras, slimmed base deps, ruff path fixes, exclude TS artifacts from wheel
• Update README / REPRODUCE.md; bump version (import paths change)

Acceptance

Both install commands succeed; bare install works without detection deps; tests/ruff/mypy green; wheel contains no TS/npm files; existing CLI commands unchanged.

Out of scope: PatchLoop Python wrapper/port (separate issue).

🤖 Generated with Claude Code