Add sssf skill, installable via the skills CLI

Port the sssf skill from ~/.agents/skills/sssf into this repo so it can be
distributed and installed with the skills CLI (skills add INDigitalStudio/skills
--skill sssf).

- Copy the skill (SKILL.md, cookbooks, references, scripts, templates, and the
  visualizer app source) into sssf/.
- Gitignore build/runtime artifacts: the visualizer's node_modules/ and dist/,
  Python bytecode, and the machine-specific repos.json.
- Make the skill location-independent: install.py now stamps the skill's real
  path into the stamped justfile's skill_dir (replacing the hardcoded
  ~/.agents/skills/sssf), so 'just obs' finds the visualizer wherever the CLI
  installed the skill.
- Update cookbooks to use <skill>/scripts/... instead of the hardcoded path,
  and document the skills CLI install command.
- Update the repo README with install instructions.

sssf/templates/adws/adw_build_test.py

@@ -0,0 +1,79 @@
+#!/usr/bin/env -S uv run
+# /// script
+# dependencies = ["pydantic", "python-dotenv", "pyyaml", "rich"]
+# ///
+"""ADW Build Test — implement, then verify; failures flow back into the builder.
+
+Usage:
+    uv run adws/adw_build_test.py "<prompt or path/to/prompt.md>" [--config adws/adw_sssf_config/sssf.config.yaml] [--adw-id a1b2c3d4]
+
+Phases: engineer(request) -> builder -> code(test) [-> builder(fix) -> code(test) ... bounded]
+
+Testing is CODE. The suite's command is written down in adw_modules/quality.py,
+so running it needs no judgement — only repairing it does. Failures reach the
+builder as an envelope through `quality.as_envelope`, which is the same door an
+agent's report came through, so the repair loop is unchanged.
+
+A failing suite does NOT fail its phase: the runner did its job, the code is
+what failed. It fails the run, checked at the end, after the bounded fix loop
+has had its chances.
+"""
+
+import argparse
+import sys
+
+from adw_modules import agents, gates, quality, session, utils
+from adw_modules.data_types import AgentCall, BuildOutput, PhaseParams
+
+REQUIRED_AGENTS = ["builder"]
+MAX_FIX_LOOPS = 3
+
+
+def main(prompt: str, config: str = "adws/adw_sssf_config/sssf.config.yaml", adw_id: str | None = None) -> int:
+    cfg = agents.load_config(config)
+    agents.validate(cfg, REQUIRED_AGENTS)
+    run = session.ensure(cfg, adw_id)
+
+    def record(ph, result) -> None:
+        passed = sum(1 for check in result.checks if check.passed)
+        ph.log(passed=result.passed, checks=f"{passed}/{len(result.checks)}",
+               artifacts=", ".join(result.artifacts))
+
+    with run.phase(PhaseParams(name="request", kind="engineer", owner=run.engineer,
+                               description="Capture the incoming ask")) as ph:
+        ph.log(input=prompt)
+
+    with run.phase(PhaseParams(name="build", kind="agent", owner="builder",
+                               description="Implement the request")) as ph:
+        previous = ph.call(AgentCall(output_type=BuildOutput, prompt=prompt,
+                                     gates=[gates.diff_matches_claims]))
+
+    test = None
+    for i in range(1, MAX_FIX_LOOPS + 1):
+        with run.phase(PhaseParams(name=f"test_{i}", kind="code", owner="quality",
+                                   description="Run the suite — a known command, so code runs "
+                                               "it and no agent has to rediscover it")) as ph:
+            test = quality.run_tests(run)
+            record(ph, test)
+
+        if test.passed:
+            break
+
+        with run.phase(PhaseParams(name=f"fix_{i}", kind="agent", owner="builder", retries=1,
+                                   description="Repair what the suite reported, from its "
+                                               "verbatim output")) as ph:
+            previous = ph.call(AgentCall(output_type=BuildOutput, prompt=prompt,
+                                         previous=quality.as_envelope(test, "tests"),
+                                         gates=[gates.diff_matches_claims]))
+
+    return run.finish(accepted=test is not None and test.passed,
+                      reason=f"the suite still failed after {MAX_FIX_LOOPS} fix attempt(s)")
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("prompt", help="inline text or a path to a prompt file")
+    parser.add_argument("--config", default="adws/adw_sssf_config/sssf.config.yaml")
+    parser.add_argument("--adw-id", default=None, help="join or pin an existing session")
+    args = parser.parse_args()
+    sys.exit(main(utils.resolve_prompt(args.prompt), args.config, args.adw_id))