feat(frontend): remove amp from agentOS agent catalog

[NicholasKissel]

• Remove Amp (Sourcegraph) from the agentOS "Choose your agent" onboarding step, leaving Pi, Claude Code, Codex, and OpenCode.

[railway-app]

🚅 Deployed to the rivet-pr-5519 environment in rivet-frontend

Service	Status	Web	Updated (UTC)
frontend-cloud	😴 Sleeping (View Logs)	Web	Jul 31, 2026 at 1:03 am
frontend-inspector	😴 Sleeping (View Logs)	Web	Jul 31, 2026 at 1:01 am
website	😴 Sleeping (View Logs)	Web	Jul 31, 2026 at 1:01 am
kitchen-sink	😴 Sleeping (View Logs)	Web	Jul 31, 2026 at 1:01 am
ladle	✅ Success (View Logs)	Web	Jul 31, 2026 at 12:54 am
mcp-hub	✅ Success (View Logs)	Web	Jul 31, 2026 at 12:52 am

[claude]

Review

Small, clean, well-scoped change. The catalog entry for amp is fully removed, the comment above AGENTS is updated to match, and I confirmed there are no other dangling references to the amp slug or @rivet-dev/agent-os-amp package elsewhere in the repo (docs, website registry, icons, etc.).

Code quality: No issues. Matches the existing pattern for AgentEntry objects in catalog.ts.

Bugs: None found. Removing an "available" entry with no other consumers of the amp slug (e.g., no persisted user selections keyed by slug that would now dangle) is safe for a client-only onboarding catalog like this.

Performance / Security: Not applicable for this change.

Test coverage: No tests exist for this catalog file and none are needed for a static data removal like this.

One minor note (non-blocking): per catalog.ts's own header comment, this curated list drifts from the canonical registry at website/src/data/registry.ts. Worth double-checking that Amp is also removed/marked appropriately there if it's meant to stay in sync, though that may be intentionally out of scope for this PR.