User command shortcuts landed in the command surface

Kaji now supports user-defined command shortcuts that can be parsed, validated, previewed, resolved, and launched from the Ask palette. The shortcut reference UI also gained a dedicated section so custom commands are easier to discover.

• Added UserCommandShortcut models and resolved command templates
• Added parser, resolver, validator, preview builder, argument binder, and store services
• Added user command shortcut settings rows and form UI
• Added Ask palette integration for user command shortcuts
• Added parser, resolver, store, template, and palette tests

Parent Agent sessions keep their tab scope

Parent Agent state now preserves tab scope and session identity more carefully across workspace snapshots. Agent run details are also persisted in the V2 snapshot path.

• Updated AppState and workspace snapshot handling for Parent Agent tab scope
• Persisted agent run details in V2 snapshots
• Updated OpenCode plugin runtime handling
• Added AppStateParentAgentTests and AgentRunPersistenceV2Tests

Browser lifecycle cleanup got sturdier

The CEF browser runtime received lifecycle and cleanup hardening so browser sessions recover and discard inactive work more predictably.

• Improved KajiBrowserRuntimeCoordinator behavior
• Added KajiCEFProfileRecovery tests
• Added browser inactive discard policy coverage
• Updated browser controller registry and pane cleanup paths
• Bumped Kaji to 0.2.7