fix(contracts): tolerate unknown keybinding commands on client decode

[bulgadev]

Problem

When a T3 Code server introduces new keybinding commands (e.g. filePicker.toggle, projectSearch.toggle), clients built against an older contracts build fail to decode the entire server.getConfig response because ResolvedKeybindingsConfig uses a closed union (KeybindingCommand) that rejects unknown values.

This manifested in the VS Code extension as:

T3 Code pairing failed: Could not connect to T3 Code: Expected "sidebar.toggle" | "terminal.toggle" | ... | "thread.jump.9", got "filePicker.toggle" at ["value"]["keybindings"][42]["command"]

The pairing itself succeeded (bearer token exchanged and stored), but the subsequent getConfig RPC failed during schema validation, blocking the connection.

Solution

Make the decode side of ResolvedKeybindingsConfig forward-compatible: rules whose command does not match the known union are silently dropped on decode, while known rules round-trip unchanged. Encoding is unaffected, so the server (which only ever emits known commands) and the strict authoring path (KeybindingRule / KeybindingsConfig) keep their exact behavior.

This is the same forward-compat pattern used elsewhere in the codebase (e.g. ProviderOptionSelections in model.ts tolerates legacy shapes via Schema.decodeTo + transformOrFail).

Scope

ResolvedKeybindingsConfig is consumed by all four wire schemas that carry resolved keybindings:

• server.getConfig (initial config fetch)
• subscribeServerConfig (config stream)
• serverUpsertKeybinding / serverRemoveKeybinding (mutation results)

All three clients (vscode, web, mobile) share the same RpcClient.make(WsRpcGroup) decode path, so this fix unblocks all of them simultaneously.

Changes

• packages/contracts/src/keybindings.ts: wrap ResolvedKeybindingsConfig with a decodeTo transform that filters unknown rules via Schema.decodeUnknownOption(ResolvedKeybindingRule) per element.
• packages/contracts/src/keybindings.test.ts: two new tests verifying unknown commands are dropped and all-unknown arrays decode as empty.

Verification

• pnpm --filter @t3tools/contracts test: 238 tests passed (19 files)
• pnpm exec vp check packages/contracts/src/keybindings.ts packages/contracts/src/keybindings.test.ts: 0 errors, 0 warnings
• ELECTRON_SKIP_BINARY_DOWNLOAD=1 pnpm exec vp run -r --cache --log labeled typecheck: exit 0

[patroza]

Thanks a lot for the contribution!

Requesting changes:

• decodeUnknownOption(ResolvedKeybindingRule) drops every invalid rule, not only rules with unknown commands. Malformed rules using known commands should continue to fail validation; only genuinely unknown command names should be skipped.
• The maximum-length check runs after filtering. A large input containing unknown or malformed rules can decode to an empty array and bypass the 256-rule limit. Please enforce the limit on the input array before filtering.