[iamnbutler]

Closes the "Insertion outside text fields" gap. desktop_insert now has a typing route for receivers whose text can't be observed: terminals, canvases, custom views, and web editors that expose no AX text.

Why typing and not a guarded paste

• The paste transaction restores the clipboard only after it observes consumption.
• Until then it keeps a paste reservation, and that reservation refuses every later automated clipboard write until the receiver's process exits.
• A receiver with no readable text can never prove consumption. Every paste into one would therefore wedge the clipboard gate for as long as the target app runs.
• Changing that would weaken the restore rules, which this change keeps as they are.
• Typing doesn't touch the clipboard at all.

Route choice (made before dispatch)

• Typing can't be a fallback after a refused paste: the host consumes the snapshot when literalInsert refuses.
• The snapshot reports a focused control → paste, unchanged.
• No focused control → type into the window's keyboard focus (receiver: window_focus).
• New optional route:
  • "type" types into an observed control whose text can't be read, such as a terminal's text area (receiver: observed_control).
  • "paste" refuses typing.

Admission

• This reuses feat: send keys to windows whose focus isn't an observed control #51's window-focus admission. Typing calls upstream's typeActionsWithOutcome(expectedWindowIdentity:expectedWindowBounds:). Before every character it runs requireExactWindowKeyboardFocus: the app's focused element must be inside the window, and the window must be the app's key window.
• With route: "type" and an observed control, typing uses the ExactWindowKeyboardTarget variant, bound to that control.
• The runtime allowlist gains .exactWindowTargetedTypeActions. This is a host change, so an older host refuses with an "update the runtime" message. No bridge op is added, so the op count stays at 127.

Guards

• Typed text is limited to 1,000 UTF-16 units, because focus is validated per character.
• Newlines, tabs and other control characters are refused, since typing them presses Return or Tab. A terminal would run the line. The hint points to desktop_key.
• Refused while IsSecureEventInputEnabled() is true (password fields, Terminal's Secure Keyboard Entry).
• Cadence is a fixed 2 ms.

Outcome

• A typed insertion is unknown (INSERTION_UNVERIFIED) unless the host reports confirmedChange for an observed control.

Docs: the tool description, the docs/tools.md row, a new paragraph, and the Not-supported bullet (now "Confirmed insertion outside text fields").

Checks

• npm run check and the native build pass.
• Pending: screen locked. Live typing into Terminal, a canvas and a contenteditable. Timing for 1,000 characters. The secure-input refusal. These also need a dev host, because the installed host doesn't allow the typing op.