v0.6.3

fix(forge): hoist staged ACP node_modules to stay under Windows MAX_PATH

The Squirrel/nuget Windows maker failed with 'path too long': stageAcpAdapters
rebuilt the ACP dependency closure by always nesting each dep under its parent,
producing 5-level chains (codex-acp -> open -> wsl-utils -> is-wsl ->
is-inside-container -> is-docker) whose paths hit ~260 chars on the CI runner and
blew past Windows' MAX_PATH (nuget.exe ignores long-path settings).

Hoist every package to the top-level node_modules npm-style, nesting only on a
genuine version conflict. Deepest staged path drops 177 -> 114 chars (worst-case
CI absolute ~197, well under 260). Add verifyAcpStaging() which asserts every
dependency edge resolves, in the staged tree, to the same version as the source
pnpm tree, failing the build loudly instead of shipping a broken installer.