DevEx: phpc init — scaffold minimal web project (phpc.json + public/)

[PurHur]

Problem

Contributors scaffolding #246 MiniWebApp, #274 example phpc.json, and #67 reference app hand-copy directory layouts. There is no phpc init command; ProjectManifest (#106) already reads phpc.json for phpc serve --aot, but new projects start from scratch.

Goal

phpc init [target-dir] writes a minimal, lint-clean web project:

target/
  phpc.json          # entry, binary, optional docroot
  public/
    index.php        # hello + htmlspecialchars
  README.md          # phpc run / serve / build commands

Defaults should match #274 manifest shape and pass phpc lint public/index.php on a fresh clone.

Scope

• Subcommand in bin/phpc.php with --force to overwrite
• Template files under templates/init/ or inline strings in phpc CLI
• Generated phpc.json: "entry": "public/index.php", "binary": ".phpc/bin/app"
• Document in README quick start (cross-link Docs: examples/README — phpc/vm/aot run matrix per example folder #262, DevEx: phpc run — document -q / -p web superglobals in CLI help #268)
• test/unit/PhpcInitTest.php: run init in temp dir, assert files exist, phpc lint exit 0

Acceptance criteria

cd /tmp && rm -rf demo-app && mkdir demo-app && cd demo-app
/path/to/phpc init .
phpc lint public/index.php
phpc run public/index.php

Exit 0; output contains Hello.

Verification (local / Docker only)

docker run --rm -v "$(pwd):/compiler" -w /compiler php-compiler:22.04-dev \
  vendor/bin/phpunit --filter PhpcInitTest

Dependencies

• DevEx: phpc.json project manifest (entry, includes, public assets) #106 / DevEx: phpc.json JSON Schema and phpc validate-manifest #263 full manifest schema (init may emit minimal subset only)
• Examples: Minimal phpc.json for 001-SimpleWeb and 002-StaticWeb #274 example manifests (keep in sync)
• DevEx: phpc lint --all for project trees (MiniWebApp blocker report) #286 phpc lint --all (future: init + lint whole tree)

Links

• lib/Web/ProjectManifest.php, bin/phpc.php
• 🗺️ ROADMAP: Self-host + web-capable PHP subset (living) #78 ROADMAP Phase 0 (Foundation)
• Reference: MiniWebApp lint-first skeleton (examples/003-MiniWebApp) #246 MiniWebApp skeleton

[PurHur]

Merged via #339: phpc init scaffolds phpc.json, public/index.php, and README.md with PhpcInitTest coverage.