specclaw v0.5.2 — Grounded context discovery + prompt hardening

Two releases since v0.5.0, bundled here. Headline: specclaw now grounds agents in your repo's own docs and hardens every agent payload with evidence-first prompting.

✨ Grounded context discovery (#37, 0.5.2)

• specclaw-discover-context — auto-discovers project docs repo-wide (git ls-files + find fallback) and injects a budget-capped digest into plan/build/verify. Ranks llms.txt/llms-full.txt first, then root docs, doc dirs, nested READMEs. Excludes changelogs, licenses, deps, archive/deprecated/i18n, .specclaw/. New context: config block (discovery, max_lines, folders, pin, exclude) with Context7-style precedence. Over-budget files named in the footer — nothing dropped silently. context.discovery: false restores prior behavior.
• Plan grounding — /specclaw:plan builds a codebase survey, reads the docs digest, applies promoted spec-guidelines.md, and records sources in design.md.
• Discovery regression tests — 11 jq-free assertions over a fixture tree.

🔒 Prompt hardening (#37, 0.5.2)

Evidence-grounded agent payloads (sourced from Anthropic + OpenAI prompt guides):

• Verify + code-reviewer use quote-first verdicts — no quotable evidence → finding dropped.
• Build/fix payloads gain Working Rules (investigate before answering, general-purpose solutions, temp cleanup) and reversibility rules (no force-push, no git reset --hard, no --no-verify — halt + escalate instead).
• Build payload reordered task-last (long-context win); constraints now carry motivations; few-shot good/bad examples added.

🌿 Smart base branch detection (#37, 0.5.2)

• New detect_base_branch() — git.base_branch override → origin/HEAD (self-healing) → gh default → main/master.
• specclaw-build setup branches from origin/<base> (not arbitrary HEAD); finalize merges into the detected base; specclaw-pr no longer hardcodes --base main.

🔔 Plugin update check (#36, 0.5.1)

• specclaw-check-update — /specclaw:status surfaces a one-line hint when a newer plugin version is published (vs the repo's raw marketplace.json). Network ≤ once/24h, 5s timeout, fail-silent. Gate: plugin.update_check (default true).

📝 Docs (#33)

• Fixed stale CONTRIBUTING.md references.

Full changelog: v0.5.0...v0.5.2