feat(kilo): add provider and model management

[markos-ttl]

Summary

• teach the existing custom:kilo ACP agent to read and write Kilo's native config and auth files
• add Kilo Code provider connection, model discovery, ordering, and collapse controls in Agent SDK Management
• add Kilo-only provider grouping and model/reasoning management to the chat model selector
• localize the new settings across all 10 message catalogs

Architecture

Kilo remains an upstream custom ACP agent. This does not add a built-in AgentType, parser, registry entry, MCP integration, or session-history implementation.

Validation

• pnpm eslint .
• pnpm test — 306 files, 4,086 tests passed
• pnpm build
• cargo check
• cargo test --features test-utils -- --skip commands::folders::tests::remove_worktree_deletes_a_branch_plain_delete_cannot
• cargo check --no-default-features --bin codeg-server
• cargo test --no-default-features --bin codeg-server --lib -- --skip commands::folders::tests::remove_worktree_deletes_a_branch_plain_delete_cannot
• cargo check --no-default-features --bin codeg-mcp
• desktop/server/MCP Clippy pass with clippy::collapsible_match allowed; strict upstream Clippy currently reports three pre-existing warnings in parsers/codex.rs, parsers/pi.rs, and work_task/engine.rs

The skipped worktree test is unrelated to this change and fails on this macOS Git version only because the assertion expects lowercase cannot while Git emits Cannot.