refactor: derive command exposure lists from descriptors

[thymikee]

Summary

Derive MCP exposure and capability-checked CLI command lists from command descriptors.
Remove the hand-maintained catalog exposure/exemption sets, keep command identity in the catalog, and document the remaining descriptor ownership boundary.

Closes #1136

Validation

• pnpm format
• pnpm exec vitest run src/core/command-descriptor/__tests__ src/utils/__tests__/command-schema-guards.test.ts src/commands/__tests__/command-surface-metadata.test.ts src/mcp/__tests__/router.test.ts
• pnpm check:quick
• pnpm check:fallow --base origin/main

[github-actions]

Size Report

Metric	Base	Current	Diff
JS raw	1.6 MB	1.6 MB	-51 B
JS gzip	500.0 kB	499.9 kB	-51 B
npm tarball	596.9 kB	596.9 kB	-74 B
npm unpacked	2.1 MB	2.1 MB	-51 B

Startup median (7 runs, lower is better):

Scenario	Base	Current	Diff
CLI --version	28.0 ms	28.0 ms	+0.0 ms
CLI --help	54.1 ms	53.8 ms	-0.2 ms

Top changed chunks:

Chunk	Raw diff	Gzip diff
dist/src/sdk-batch.js	-61 B	-55 B
dist/src/internal/daemon.js	0 B	+5 B
dist/src/device-rotation.js	0 B	+2 B
dist/src/runtime.js	0 B	-2 B
dist/src/session.js	0 B	-1 B

[thymikee]

Reviewed #1137 at head e35728b against #1136 and ADR 0008. No actionable blockers found.

Checked:

• src/command-catalog.ts no longer owns the MCP exposure and capability-check hand lists; it keeps command identity.
• src/core/command-descriptor/registry.ts derives MCP exposure from descriptors, keeps prepare explicitly unexposed, and represents local client-backed debug, metro, and session without giving them daemon routes or capabilities.
• deriveDaemonCommandDescriptors only includes descriptors with a daemon facet, so local MCP commands do not enter daemon routing.
• deriveStructuredBatchCommandNames still only uses batchable, and the added local commands are not batchable.
• listCommandMetadata, MCP router, and schema guard tests consume the registry projection and fail fast if descriptor-exposed commands lack metadata or executable definitions.
• CI is green across 21 checks.

Residual note: the monitor guidance references plans/perfect-shape.md, but that file is absent on this checkout/ref. I reviewed against the embedded checklist, #1136, and ADR 0008 instead.