Add screen-size command

[jfperusse]

Issue

Agents driving Codea through codea could screenshot a project only at whatever
size the viewer happened to be. Checking a layout at another size or orientation
meant changing the viewer by hand on the device, which is exactly what the CLI
exists to avoid.

Fix

Adds codea screen-size [preset] over the setScreenSize/getScreenSize MCP
tools, accepting the five viewer preset ids verbatim:

codea screen-size                     # Screen size: tv — TV (16:9), 1920 × 1080
codea screen-size iphone-landscape    # set it

Shaped after idle-timer/paused rather than runtime: the presets apply to
the viewer, not to a project, so there is no project argument. Preset ids are
validated client-side, so a typo fails with the valid list and no round trip,
and the id → display name mapping lives in the CLI so the reported id stays the
contract.

Reading the size is a live query, not a stored setting. getScreenSize
returns {"preset": id} plus width and height once the viewer has laid
out, and those are its laid-out bounds rather than the preset's nominal size.
Under match-display it should therefore follow the window, though that is an
expectation rather than something observed — see Tests. Dimensions are omitted
rather than null before first layout, so the command prints the preset alone in
that case.

No --json flag: this CLI has none anywhere, and adding one here would have
made screen-size the odd command out.

Depends on

Do not merge before the app half ships, or a released codea advertises a
command no shipped Codea answers. The MCP tools exist only in
codea PR #440,
so until that merges and reaches a build, this command fails with an
unknown-tool MCP error for everyone.

Tests

cargo fmt clean, no new clippy warnings, 13 unit tests pass — the parser is
covered for dimensions present, omitted, half-present and fractional, and for a
bare id or a missing preset now being an error.

Verified on an iPad Pro (iPad14,5, iOS 26.7) against a local build of #440,
re-run after the read contract changed to JSON. All five presets, read back
through the parser:

preset	reported
match-display	1590 × 1192
iphone-portrait	393 × 852
iphone-landscape	852 × 393
tv	1920 × 1080
square	1112 × 1112

These agree to the pixel with WIDTH/HEIGHT read inside Lua in an earlier
run — two independent sources. That the size comes from laid-out bounds rather
than a preset table is also proven directly: ResizableRenderer.Preset.width
is 0 for tv, square and matchWindow, yet tv reports 1920 × 1080.

Both reachable failures print their message and exit 1: no project running, and
an unknown preset, the latter rejected client-side with no round trip.

Two branches are deliberately untested because neither can be reached here.
The non-Pro path is unreachable by design — the Air Code server only starts for
Pro subscribers, so a non-Pro user cannot reach any MCP tool at all. The
absent-dimensions path has never been seen to fire: polling after codea run
returns "no project is running" until the size is already present. Both are
kept anyway, since reporting a wrong or zero size would be worse than handling
a case that may occur on a slower device. Likewise, match-display following
the window is expected from the renderer tracking view bounds but was not
observed — the two levers available remotely, viewer.mode = FULLSCREEN and
sliding the output pane, both overlay the viewer rather than inset it, and a
real resize needs Stage Manager or split view.

Also folds in a changelog and cargo release configuration, and removes the
[package.metadata.release] section from Cargo.toml so release.toml is the
only home for that config: cargo-release 1.1.6 gives the Cargo.toml section
precedence, so editing the duplicated keys in release.toml silently did
nothing. Verified by dry run that the tag, the changelog replacements,
publish = false and allow-branch all behave from release.toml alone.

🤖 Generated with Claude Code

https://claude.ai/code/session_014kJYH24sqV9xNvhVb86bMZ