fix(desktop): keep command palette responsive and scoped

[Hona]

• Match built-in commands synchronously; append file and session results independently without resetting keyboard selection.
• Register commands only for committed page owners, and separate file-panel closing from application-tab closing. This prevents duplicate registrations and stale session actions in drafts.
• Handle event-driven read failures at their owner, preserve explicit API rejections, and render toast icons under a Solid owner. Keep diagnostic logging enabled.
• Give the development picker a browser-loadable HTTP script URL instead of exposing a virtual: import.

flowchart LR
  Input[Palette input] --> Commands[Local command matches]
  Input --> Files[File search]
  Input --> Sessions[Debounced session search]
  Commands --> Results[Selectable results]
  Files -.-> Results
  Sessions -.-> Results

Loading

Lookup latency

Query	Before: v2 at 1ae2cf3567	After: PR
Copy Session ID	110.8 ms	2.2 ms
Home: Open settings	113.3 ms	1.5 ms

• Median of five runs in production Chromium on Windows, with immediate fixture responses. Measures input to the selected-result DOM update, not packaged Electron startup.

While remote searches remain pending

Before	After

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