feat: complete GeneralUpdate Skill CodeGen v2 — 7 skills, BM25 search, 336 codegen combos, CLI (#15)

* feat: complete GeneralUpdate Skill CodeGen v2 upgrade

This PR delivers a comprehensive upgrade transforming the skill suite from
a documentation-driven reference into an automated development toolkit.

- Parameterized code generator (336 combinations: 6 strategies x 7 frameworks x 2 Bowl x 4 scenes)
- BM25 search engine with 51 known issues database (8C + 11H + 20M + 12L)
- CLI skeleton: gskill init/uninstall/generate/versions/update (5 commands)
- Multi-platform support: 10 AI platform configs (Claude, Cursor, Windsurf, etc.)
- Single-command sync: _sync_all.py with --apply/--verify modes

- Root SKILL.md: developer roadmap, 5-question decision tree, anti-patterns
- All 5 sub-skill SKILL.md: narrative workflows, pre-delivery checklists, anti-pattern tables
- CLAUDE.md: AI agent development guide
- Architecture docs: src -> CLI sync rules

- Step-by-step narrative workflows (Step 1 -> Step 2 -> Step 3)
- User requirements extraction templates in every SKILL.md
- Pre-Delivery Checklists + Anti-Pattern lists for every sub-skill
- Structured output format (decision reasons + warnings + checklist)

- generalupdate-migration: v9.x -> v10 / dev-branch -> stable migration path
- generalupdate-security-audit: 14-point security audit matrix

- CI workflow: Python search test, codegen validation, .NET build, TypeScript check
- Release workflow: full validate -> changelog -> GitHub Release

- Fixed Dispatcher ambiguity in MVVM listener templates
- Fixed WinForms 'this' scope in event listeners
- Fixed MAUI missing using declarations
- Fixed CLI init only installed 1 skill (now installs all 7)
- Fixed CLI uninstall targeted scope
- Fixed project-scaffold {{PLACEHOLDER}} leakage

Co-Authored-By: Claude <noreply@anthropic.com>

* chore: add .gitignore for __pycache__

* fix: resolve all 19 Copilot review comments

- fix: 'bate' → 'beta' typo in skill.json, plugin.json, marketplace.json
- fix: skill.json version desc v10.4.6 → v10.5.0-beta.4
- fix: template.ts missing readFile import, platform path hardcoding
- fix: init.ts --ai all now routes to generateAllPlatformFiles
- fix: generate.ts command injection (execSync→spawnSync+argv)
- fix: extract.ts path injection (exec→execFile)
- fix: _sync_all.py filecmp shallow=False + --verify detects NEEDS SYNC
- fix: release.yml Windows paths on Linux runner
- fix: sync CLI assets after source changes

Co-Authored-By: Claude <noreply@anthropic.com

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: JusterZhu

.claude-plugin/marketplace.json

@@ -0,0 +1,39 @@
+{
+  "name": "generalupdate-skill-codegen",
+  "id": "generalupdate-skill-codegen",
+  "owner": {
+    "name": "JusterZhu"
+  },
+  "metadata": {
+    "description": ".NET auto-update skill suite — 7 skills for GeneralUpdate: scaffolding, UI, strategy, advanced, troubleshooting (50+ issues), migration, and security audit",
+    "version": "0.0.1-beta.1"
+  },
+  "plugins": [
+    {
+      "name": "generalupdate-skill",
+      "source": "./",
+      "description": "Complete GeneralUpdate (.NET auto-update) integration skill suite. Generates dual-project scaffolding, full-state update UI (6 frameworks), 6 update strategies decision tree (Client-Server/OSS/Silent/Differential/CVP/Push), advanced extension points (Bowl crash daemon, IPC replacement, AOT), BM25-powered troubleshooting search (50+ known issues), v9.x→v10 migration guide, and 14-point security audit matrix. All templates target NuGet v10.5.0-beta.4.",
+      "version": "0.0.1-beta.1",
+      "author": {
+        "name": "JusterZhu"
+      },
+      "keywords": [
+        "generalupdate",
+        "auto-update",
+        "dotnet",
+        ".net",
+        "wpf",
+        "avalonia",
+        "maui",
+        "update",
+        "upgrade",
+        "bootstrap",
+        "bowl",
+        "differential",
+        "nuget"
+      ],
+      "category": "code-generation",
+      "strict": false
+    }
+  ]
+}

.claude-plugin/plugin.json

@@ -0,0 +1,32 @@
+{
+  "name": "generalupdate-skill",
+  "description": "Complete .NET auto-update skill suite for GeneralUpdate. 7 skills covering: Bootstrap scaffolding, update UI (6 frameworks), 6 strategies (Client-Server/OSS/Silent/Differential/CVP/Push), advanced extension points (Bowl, IPC, AOT), 50+ known issues diagnosis with BM25 search engine, version migration, and security audit. All templates target NuGet v10.5.0-beta.4.",
+  "version": "0.0.1-beta.1",
+  "author": {
+    "name": "JusterZhu"
+  },
+  "license": "Apache-2.0",
+  "keywords": [
+    "generalupdate",
+    "auto-update",
+    "dotnet",
+    ".net",
+    "wpf",
+    "avalonia",
+    "maui",
+    "winforms",
+    "bootstrap",
+    "bowl",
+    "differential",
+    "nuget"
+  ],
+  "skills": [
+    ".claude/skills/generalupdate-init",
+    ".claude/skills/generalupdate-ui",
+    ".claude/skills/generalupdate-strategy",
+    ".claude/skills/generalupdate-advanced",
+    ".claude/skills/generalupdate-troubleshoot",
+    ".claude/skills/generalupdate-migration",
+    ".claude/skills/generalupdate-security-audit"
+  ]
+}

.claude/scripts/_sync_all.py

@@ -0,0 +1,123 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+"""
+Sync all source artifacts from .claude/ to cli/assets/ before release.
+This is the single entry point for ensuring CLI bundles are up-to-date.
+
+Usage:
+    python3 .claude/scripts/_sync_all.py          # Dry run (verbose)
+    python3 .claude/scripts/_sync_all.py --apply   # Actually copy files
+    python3 .claude/scripts/_sync_all.py --verify  # Only check for differences
+"""
+import argparse
+import filecmp
+import os
+import shutil
+import sys
+from pathlib import Path
+
+REPO_ROOT = Path(__file__).resolve().parent.parent.parent  # .claude/scripts/ -> repo root
+CLAUDE_DIR = REPO_ROOT / ".claude"
+CLI_ASSETS_DIR = REPO_ROOT / "cli" / "assets"
+SKILL_DIR = CLAUDE_DIR / "skills"
+
+# Sync mappings: (source_relative, dest_relative, description)
+SYNC_MAP = [
+    # All 7 skills (to cli/assets/skills/)
+    ("skills", "skills", "All 7 skill directories"),
+    # Troubleshoot scripts + data (to cli/assets/scripts/ + cli/assets/data/)
+    ("skills/generalupdate-troubleshoot/scripts", "scripts", "BM25 search engine"),
+    ("skills/generalupdate-troubleshoot/data", "data", "Issues + strategies CSV"),
+    # Code generator
+    ("scripts/generate.py", "scripts/generate.py", "Parameterized code generator"),
+    ("scripts/generate", "scripts/generate", "Generator templates"),
+]
+
+
+def sync_file(src: Path, dst: Path, apply: bool, dry_run: bool) -> str:
+    """Sync one file or directory. Returns status string."""
+    if not src.exists():
+        return f"⚠️  SOURCE MISSING: {src.relative_to(REPO_ROOT)}"
+
+    if dst.exists():
+        if src.is_file():
+            up_to_date = filecmp.cmp(src, dst, shallow=False)
+        else:
+            up_to_date = _dirs_equal(src, dst)
+        if up_to_date:
+            return f"✓  UP TO DATE: {src.relative_to(REPO_ROOT)}"
+
+    if dry_run or not apply:
+        return f"→  NEEDS SYNC: {src.relative_to(REPO_ROOT)}  →  {dst.relative_to(REPO_ROOT)}"
+
+    # Apply the sync
+    dst.parent.mkdir(parents=True, exist_ok=True)
+    if src.is_file():
+        shutil.copy2(src, dst)
+    else:
+        if dst.exists():
+            shutil.rmtree(dst)
+        shutil.copytree(src, dst)
+    return f"✅  SYNCED: {src.relative_to(REPO_ROOT)}"
+
+
+def _dirs_equal(a: Path, b: Path) -> bool:
+    """Check if all files in source exist and match in destination (b may have extras)."""
+    if not b.exists():
+        return False
+
+    def _files(p: Path):
+        return sorted(
+            (f for f in p.rglob("*") if f.is_file() and "__pycache__" not in str(f)),
+            key=lambda x: str(x).lower(),
+        )
+
+    afiles = _files(a)
+
+    for fa in afiles:
+        rel = fa.relative_to(a)
+        fb = b / rel
+        if not fb.exists():
+            return False
+        if not filecmp.cmp(fa, fb, shallow=False):
+            return False
+
+    return True
+
+
+def main():
+    parser = argparse.ArgumentParser(description="Sync .claude/ source to cli/assets/")
+    parser.add_argument("--apply", action="store_true", help="Actually copy files (default: dry-run)")
+    parser.add_argument("--verify", action="store_true", help="Only check, exit 1 if out of sync")
+    args = parser.parse_args()
+
+    dry_run = not args.apply
+    if dry_run and not args.verify:
+        print("═══ DRY RUN ═══  Use --apply to actually copy\n")
+
+    statuses = []
+    all_ok = True
+
+    for src_rel, dst_rel, desc in SYNC_MAP:
+        src = CLAUDE_DIR / src_rel
+        dst = CLI_ASSETS_DIR / dst_rel
+        status = sync_file(src, dst, args.apply, dry_run)
+        statuses.append((desc, status))
+        if status.startswith("⚠️"):
+            all_ok = False
+
+    print(f"\n═══ Summary ({'DRY RUN' if dry_run else 'APPLIED'}) ═══\n")
+    for desc, status in statuses:
+        print(f"  {status}")
+
+    if args.verify:
+        needs_sync = any(status.startswith("→") for _, status in statuses)
+        if not all_ok or needs_sync:
+            print("\n❌ Verify FAILED: sources are out of sync")
+            sys.exit(1)
+        print("\n✅ Verify PASSED: all sources are in sync")
+        sys.exit(0)
+
+
+if __name__ == "__main__":
+    main()