Follow up PR #265: refine chapters, diagrams, and add S20 (#283)

* feat: s01-s14 docs quality overhaul — tool pipeline, single-agent, knowledge & resilience

Rewrite code.py and README (zh/en/ja) for s01-s14, each chapter building
incrementally on the previous. Key fixes across chapters:

- s01-s04: agent loop, tool dispatch, permission pipeline, hooks
- s05-s08: todo write, subagent, skill loading, context compact
- s09-s11: memory system, system prompt assembly, error recovery
- s12-s14: task graph, background tasks, cron scheduler

All chapters CC source-verified. Code inherits fixes forward (PROMPT_SECTIONS,
json.dumps cache, real-state context, can_start dep protection, etc.).

* feat: s15-s19 docs quality overhaul — multi-agent platform: teams, protocols, autonomy, worktree, MCP tools

Rewrite code.py and README (zh/en/ja) for s15-s19, the multi-agent platform
chapters. Each chapter inherits all previous fixes and adds one mechanism:

- s15: agent teams (TeamCreate, teammate threads, shared task list)
- s16: team protocols (plan approval, shutdown handshake, consume_inbox)
- s17: autonomous agents (idle polling, auto-claim, consume_lead_inbox)
- s18: worktree isolation (git worktree, bind_task, cwd switching, safety)
- s19: MCP tools (MCPClient, normalize_mcp_name, assemble_tool_pool, no cache)

All appendix source code references verified against CC source. Config priority
corrected: claude.ai < plugin < user < project < local.

* fix: 5 regressions across s05-s19 — glob safety, todo validation, memory extraction, protocol types, dep crash

- s05-s09: glob results now filter with is_relative_to(WORKDIR) (inherited from s02)
- s06-s08: todo_write validates content/status required fields (inherited from s05)
- s09: extract_memories uses pre-compression snapshot instead of compacted messages
- s16: submit_plan docstring clarifies protocol-only (not code-level gate)
- s17-s19: match_response restores type mismatch validation (from s16)
- s17-s19: claim_task deps list handles missing dep files without crashing

* fix: s12 Todo V2 logic reversal, s14/s15 cron range validation, s18/s19 worktree name validation

- s12 README (zh/en/ja): fix Todo V2 direction — interactive defaults to Task,
  non-interactive/SDK defaults to TodoWrite. Fix env var name to
  CLAUDE_CODE_ENABLE_TASKS (not TODO_V2).
- s14/s15: add _validate_cron_field with per-field range checks (minute 0-59,
  hour 0-23, dom 1-31, month 1-12, dow 0-6), step > 0, range lo <= hi.
  Replace old try/except validation that only caught exceptions.
- s18/s19: add validate_worktree_name() to remove_worktree and keep_worktree,
  not just create_worktree.

* fix: align s16-s19 teaching tool consistency

* fix pr265 chapter diagrams

* Add comprehensive s20 harness chapter

* Fix chapter smoke test regressions

* Clarify README tutorial track transition

---------

Co-authored-by: Haoran <bill-billion@outlook.com>

s08_context_compact/images/compact-overview.svg

@@ -0,0 +1,138 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 820 520" font-family="system-ui, -apple-system, sans-serif">
+  <defs>
+    <marker id="arrow" viewBox="0 0 10 10" refX="10" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse">
+      <path d="M 0 0 L 10 5 L 0 10 z" fill="#555"/>
+    </marker>
+    <marker id="arrow-blue" viewBox="0 0 10 10" refX="10" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse">
+      <path d="M 0 0 L 10 5 L 0 10 z" fill="#2563eb"/>
+    </marker>
+    <marker id="arrow-amber" viewBox="0 0 10 10" refX="10" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse">
+      <path d="M 0 0 L 10 5 L 0 10 z" fill="#d97706"/>
+    </marker>
+    <marker id="arrow-green" viewBox="0 0 10 10" refX="10" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse">
+      <path d="M 0 0 L 10 5 L 0 10 z" fill="#16a34a"/>
+    </marker>
+    <marker id="arrow-red" viewBox="0 0 10 10" refX="10" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse">
+      <path d="M 0 0 L 10 5 L 0 10 z" fill="#dc2626"/>
+    </marker>
+    <linearGradient id="header" x1="0" y1="0" x2="1" y2="0">
+      <stop offset="0%" stop-color="#1e3a5f"/>
+      <stop offset="100%" stop-color="#2563eb"/>
+    </linearGradient>
+  </defs>
+
+  <!-- 背景 -->
+  <rect width="820" height="520" fill="#fafbfc" rx="8"/>
+
+  <!-- 标题 -->
+  <rect x="0" y="0" width="820" height="48" fill="url(#header)" rx="8"/>
+  <rect x="0" y="40" width="820" height="8" fill="url(#header)"/>
+  <text x="410" y="31" fill="#fff" font-size="16" font-weight="700" text-anchor="middle">Context Compact — 压缩插在 LLM 调用前，三种触发模式</text>
+
+  <!-- 标签 -->
+  <text x="50" y="74" fill="#94a3b8" font-size="11" font-weight="600">s07 保留</text>
+  <text x="180" y="74" fill="#d97706" font-size="11" font-weight="600">s08 新增</text>
+
+  <!-- ===== ① messages[] ===== -->
+  <rect x="40" y="132" width="100" height="52" rx="8" fill="#f0f4ff" stroke="#2563eb" stroke-width="1.5"/>
+  <text x="90" y="155" fill="#1e3a5f" font-size="12" font-weight="600" text-anchor="middle">messages[]</text>
+  <text x="90" y="172" fill="#64748b" font-size="9" text-anchor="middle">(s07 保留)</text>
+
+  <!-- messages → 管线入口 -->
+  <line x1="140" y1="158" x2="168" y2="158" stroke="#d97706" stroke-width="2" marker-end="url(#arrow-amber)"/>
+
+  <!-- ===== ② 压缩管线（内部只放标签，不画路径线） ===== -->
+  <rect x="170" y="82" width="200" height="252" rx="10" fill="#fffbeb" stroke="#d97706" stroke-width="2"/>
+  <text x="270" y="102" fill="#92400e" font-size="11" font-weight="700" text-anchor="middle">压缩管线</text>
+
+  <!-- ── ① 每轮自动 ── -->
+  <rect x="186" y="110" width="168" height="16" rx="3" fill="#fde68a" stroke="#d97706" stroke-width="0.8"/>
+  <text x="270" y="122" fill="#92400e" font-size="8" font-weight="700" text-anchor="middle">① 每轮自动 · 无条件 · 0 API</text>
+
+  <rect x="186" y="130" width="168" height="24" rx="4" fill="#fef3c7" stroke="#d97706" stroke-width="1"/>
+  <text x="270" y="146" fill="#92400e" font-size="10" font-weight="600" text-anchor="middle">L3 tool_result_budget</text>
+
+  <rect x="186" y="158" width="168" height="24" rx="4" fill="#fef3c7" stroke="#d97706" stroke-width="1"/>
+  <text x="270" y="174" fill="#92400e" font-size="10" font-weight="600" text-anchor="middle">L1 snip_compact</text>
+
+  <rect x="186" y="186" width="168" height="24" rx="4" fill="#fef3c7" stroke="#d97706" stroke-width="1"/>
+  <text x="270" y="202" fill="#92400e" font-size="10" font-weight="600" text-anchor="middle">L2 micro_compact</text>
+
+  <!-- ↓ → ◇ -->
+  <line x1="270" y1="210" x2="270" y2="222" stroke="#555" stroke-width="1.2" marker-end="url(#arrow)"/>
+
+  <!-- ◇ 判断菱形（紧凑） -->
+  <polygon points="270,226 300,244 270,262 240,244" fill="#f0f4ff" stroke="#ea580c" stroke-width="1.5"/>
+  <text x="270" y="247" fill="#9a3412" font-size="7" font-weight="600" text-anchor="middle">超阈值?</text>
+
+  <!-- 否：右侧文字标注 -->
+  <text x="306" y="240" fill="#16a34a" font-size="9" font-weight="700">否 → 通过</text>
+  <text x="306" y="252" fill="#94a3b8" font-size="7">直接进 LLM</text>
+
+  <!-- 是：下方文字标注 -->
+  <text x="284" y="260" fill="#ea580c" font-size="8" font-weight="600">是↓</text>
+
+  <!-- ── ② 条件触发 ── -->
+  <rect x="186" y="268" width="168" height="16" rx="3" fill="#fed7aa" stroke="#ea580c" stroke-width="0.8"/>
+  <text x="270" y="280" fill="#9a3412" font-size="8" font-weight="700" text-anchor="middle">② 条件触发 · token 超阈值 · 1 API</text>
+
+  <rect x="186" y="288" width="168" height="24" rx="4" fill="#fed7aa" stroke="#ea580c" stroke-width="1"/>
+  <text x="270" y="304" fill="#9a3412" font-size="10" font-weight="600" text-anchor="middle">L4 compact_history</text>
+
+  <!-- 管线出口 → LLM -->
+  <line x1="370" y1="158" x2="438" y2="158" stroke="#2563eb" stroke-width="2" marker-end="url(#arrow-blue)"/>
+
+  <!-- ===== ③ LLM ===== -->
+  <rect x="440" y="132" width="100" height="52" rx="8" fill="#f0f4ff" stroke="#2563eb" stroke-width="1.5"/>
+  <text x="490" y="155" fill="#1e3a5f" font-size="14" font-weight="700" text-anchor="middle">LLM</text>
+  <text x="490" y="172" fill="#64748b" font-size="9" text-anchor="middle">stop_reason=tool_use?</text>
+
+  <!-- LLM 否 → 返回 -->
+  <line x1="490" y1="184" x2="490" y2="278" stroke="#16a34a" stroke-width="2" marker-end="url(#arrow-green)"/>
+  <text x="502" y="262" fill="#16a34a" font-size="10" font-weight="600">否</text>
+  <rect x="435" y="280" width="110" height="26" rx="13" fill="#dcfce7" stroke="#16a34a" stroke-width="1.5"/>
+  <text x="490" y="297" fill="#166534" font-size="11" font-weight="600" text-anchor="middle">返回结果</text>
+
+  <!-- LLM 是 → TOOL_HANDLERS -->
+  <line x1="540" y1="158" x2="578" y2="158" stroke="#555" stroke-width="2" marker-end="url(#arrow)"/>
+  <text x="554" y="150" fill="#64748b" font-size="10" font-weight="600">是</text>
+
+  <!-- ④ TOOL_HANDLERS -->
+  <rect x="580" y="126" width="130" height="64" rx="8" fill="#f0f4ff" stroke="#2563eb" stroke-width="1.5"/>
+  <text x="645" y="150" fill="#1e3a5f" font-size="10" font-weight="600" text-anchor="middle">TOOL_HANDLERS</text>
+  <text x="645" y="166" fill="#64748b" font-size="9" text-anchor="middle">bash · read · write</text>
+  <text x="645" y="180" fill="#64748b" font-size="9" text-anchor="middle">task · load_skill · ...</text>
+
+  <!-- LLM API 异常 → 应急压缩 → 下一轮重试 -->
+  <path d="M 535 184 L 570 216 L 580 228" fill="none" stroke="#dc2626" stroke-width="1.5" stroke-dasharray="4,3" marker-end="url(#arrow-red)"/>
+  <text x="552" y="204" fill="#991b1b" font-size="8" font-weight="600">API 异常</text>
+  <path d="M 665 266 L 665 340 L 160 340 L 160 142 L 186 142" fill="none" stroke="#dc2626" stroke-width="1.5" stroke-dasharray="4,3" marker-end="url(#arrow-red)"/>
+  <text x="530" y="328" fill="#991b1b" font-size="8" font-weight="600">重试回到压缩管线</text>
+
+  <!-- ===== ③ 异常触发（LLM API 调用失败后） ===== -->
+  <rect x="580" y="210" width="170" height="56" rx="6" fill="#fef2f2" stroke="#dc2626" stroke-width="1" stroke-dasharray="4,2"/>
+  <text x="665" y="228" fill="#991b1b" font-size="9" font-weight="700" text-anchor="middle">③ 异常触发</text>
+  <text x="665" y="242" fill="#991b1b" font-size="8" text-anchor="middle">API 返回 prompt_too_long</text>
+  <text x="665" y="256" fill="#991b1b" font-size="8" text-anchor="middle">→ reactive_compact → 重试</text>
+
+  <!-- ===== 回环（y=348 在管线框底 y=334 下方，完全不穿过） ===== -->
+  <path d="M 710 158 L 760 158 L 760 348 L 90 348 L 90 184" fill="none" stroke="#555" stroke-width="2" marker-end="url(#arrow)" stroke-dasharray="6,3"/>
+  <text x="410" y="366" fill="#64748b" font-size="10" text-anchor="middle">工具结果追加到 messages[] → 下一轮 → 再次压缩 → LLM</text>
+
+  <!-- ===== 图例 ===== -->
+  <rect x="50" y="390" width="720" height="116" rx="6" fill="#f8fafc" stroke="#e2e8f0" stroke-width="1"/>
+
+  <rect x="70" y="404" width="16" height="12" rx="3" fill="#f0f4ff" stroke="#2563eb" stroke-width="1"/>
+  <text x="94" y="414" fill="#334155" font-size="10">s07 保留：循环、hook、技能加载、子 Agent</text>
+
+  <rect x="70" y="426" width="16" height="12" rx="3" fill="#fde68a" stroke="#d97706" stroke-width="1"/>
+  <text x="94" y="436" fill="#334155" font-size="10">① 每轮自动：L3→L1→L2 在每次 LLM 调用前无条件执行，0 API</text>
+
+  <rect x="70" y="448" width="16" height="12" rx="3" fill="#fed7aa" stroke="#ea580c" stroke-width="1"/>
+  <text x="94" y="458" fill="#334155" font-size="10">② 条件触发：L3/L1/L2 跑完 token 仍超阈值 → compact_history，1 API</text>
+
+  <rect x="70" y="470" width="16" height="12" rx="3" fill="#fef2f2" stroke="#dc2626" stroke-width="1" stroke-dasharray="3,2"/>
+  <text x="94" y="480" fill="#334155" font-size="10">③ 异常触发：API 返回 prompt_too_long → reactive_compact → 重试</text>
+
+  <text x="70" y="498" fill="#94a3b8" font-size="9">三种模式的代价递增：0 API → 1 API → 1 API + 更激进的裁剪</text>
+</svg>