fix: oliver wrap subcommand not recognized (missing in parseArgs)

[drawmeanelephant]

After #112 (wrap) and #114 (plan+manifest), oliver wrap --template <file> --meta-json <json> --assets-root <prefix> --body <file> is not recognized as a subcommand and returns error.Usage (help).

• src/main.zig:52 has Command.wrap, but parseArgs at src/main.zig:200 handles render, serialize, scale, menu, meta, plan, manifest — missing wrap.
• gh api repos/drawmeanelephant/oliver/contents/src/main.zig | base64 -d | grep -n '"wrap"' shows no else if (std.mem.eql(u8, arg, "wrap")) handling.
• The wrap flag handling (--template, --meta-json, etc.) exists, but without the subcommand, it never sets command = .wrap, so parseArgs returns error.Usage for wrap.

Repro:

oliver wrap --template /tmp/t.html --meta-json /tmp/m.json --assets-root ./assets/ --body /tmp/b.html
# → usage, exit 1 (should wrap)

Fix: Add else if (std.mem.eql(u8, arg, "wrap")) { if (command != null) return error.Usage; command = .wrap; } alongside meta// in parseArgs.

Impact: Rotkeeper Phase 6 S2 (oliver wrap) is blocked on pin 9ad86a3 (oliver --version 1.0.0). S1 meta, S3 links, S4 plan, S5 manifest are green, but S2 wrap is not.

cc #108