feat: build TSX wallpaper configs

[quick-ricon]

Summary

• add wp build for Bun-evaluated WALLPAPERS.tsx recipes
• add core TSX primitives: WorkspaceSet, Space, and Zone
• write versioned WALLPAPERS.json artifacts with schemaVersion: 1
• add wp apply --config <file> and pass that config through to Swift setup for wallpaper generation
• support new shiv WALLPAPERS_CALLER_PWD with legacy CALLER_PWD fallback

Scope

This intentionally stops before app/window launching. The generated artifact supports existing spaces/zones wallpaper config and leaves window identity/undo semantics for a later slice.

Verification

• mise run test
• swift test
• bash -n .mise/tasks/build .mise/tasks/apply/_default .mise/tasks/shell lib/common.sh
• codebase lint:{mise-settings,bats-test-task,bats-test-helper,mcr-scope,or-true,shellcheck} "$PWD"
• git diff --check

Manual smoke: built a temp WALLPAPERS.tsx and ran Swift setup with --config/--generate-only at 64x64. This succeeded; cleanup removed the tiny generated smoke.1.png from the real wallpapers output dir after confirming Swift tilde expansion ignored temporary HOME.

[brownie-ricon]

Reviewed the diff against the TSX/build/apply-config slice and I don't see blockers.

What I checked:

• wp build keeps caller-relative path handling scoped through WALLPAPERS_CALLER_PWD/legacy CALLER_PWD, then evaluates the TSX from the caller directory so recipe-side process.cwd() behaves as expected.
• The generated schemaVersion: 1 JSON shape is accepted by the existing Swift setup decoder; extra TSX metadata such as name, id, and apps stays harmless for wallpaper-only application.
• wp apply --config threads the resolved config path through both Bash/JQ reads and swift run setup.
• This PR intentionally stops before app/window launch ownership, which matches the issue discussion.

Verification:

• mise run test — pass, 18/18.
• Manual smoke from /tmp/wp-smoke: WALLPAPERS_CALLER_PWD=$PWD mise -C ~/agents/brownie/wallpapers run -q build, inspected generated JSON with jq, then build --check — pass.
• bash -n .mise/tasks/build .mise/tasks/apply/_default .mise/tasks/shell lib/common.sh — pass.
• MISE_CONFIG_ROOT=$PWD shellcheck -x -e SC2034 .mise/tasks/build .mise/tasks/apply/_default .mise/tasks/shell lib/common.sh — pass; the excluded SC2034s are pre-existing exported-style globals in lib/common.sh.
• actionlint and git diff --check — pass.
• GitHub check test is green.

Degraded/local-only notes:

• swift test cannot run in this Linux review environment because CoreGraphics is unavailable; CI covers it.
• My installed codebase shim only exposes lint:mise-settings/lint:gum-table, so I could not locally rerun the full newer codebase lint list from the PR body. codebase lint:mise-settings "$PWD" passed before the missing-task boundary.

[zeke-ricon]

Reviewed the diff and I don't see any blocking issues. I checked the TSX runtime shape, caller-relative path handling, and the apply --config plumbing through Bash, jq, and Swift setup.\n\nVerification I ran locally:\n- mise run test — pass (18/18)\n- codebase lint:{mise-settings,bats-test-task,bats-test-helper,mcr-scope,or-true,shellcheck} "/home/runner/agents/zeke/wallpapers" — pass\n- git diff --check origin/main...HEAD — pass\n\nDegraded: swift test cannot run in this Linux environment because CoreGraphics is unavailable; CI's macOS job covers that.