[noodle-theo]

Adds the same three Shortcuts actions to the Mac and the iPhone for #153: Send to Agent, Open Chat and Call Agent. They have the same names, parameters and Siri phrases in both apps.

Action	Parameters	Siri phrases ("… Noodle")
Send to Agent	Agent or Group, Message (optional when files are attached), Files, Open Chat (off by default)	Send to an agent with / Send to a bot with / Send to ‹conversation› with / Send a command with / Message ‹conversation› with / Tell ‹conversation› using
Open Chat	Agent or Group (bots and groups)	Open a chat in / Open chat with ‹conversation› in / Open ‹conversation› in / Open my chat with ‹conversation› in
Call Agent	Agent (bots only)	Call an agent with / Call a bot with / Call ‹bot› with

Search keywords include "Open Chat with Agent", "Open Conversation" and "Conversation" for Open Chat, and "Send File" for Send to Agent.

Mac (commit 1, with Open Conversation renamed to Open Chat in commit 2)

• Open Chat opens a bot's or group's chat, the way clicking its notification does.
• Call Agent calls a bot and opens its chat. A bot that can't take calls only has its chat opened. A new Agent entity lists bots only.
• Send to Agent has a new Files parameter. Files are copied into the conversation the way dropped files are (storeAttachment, now shared by drop, paste and Shortcuts). With no message, the body is "Sent N attachments". Draft text and staged files are left alone. The Open Chat switch brings Noodle forward with continueInForeground after sending.

iPhone (commit 2)

• New Send to Agent action. It sends a message, files or both straight to the paired Hub with SharedSend, the same path the share extension uses. It works in the background, and the Open Chat switch brings the app forward and opens the chat by its link.
• Open Chat with Agent becomes Open Chat and also opens groups. Its conversations come from the list the app already saves for the share sheet.
• The three actions move from the widget extension into the app, so that an AppShortcutsProvider can give Siri the phrases. BotEntity is now built into both the app and the widgets. The Agent control for Control Center and the Action Button stays in the widgets, unchanged apart from sharing Shelf.bot.
• Siri's parameter values are refreshed whenever the share sheet's list changes.

Decisions:

• Keeping existing iPhone shortcuts working: the intent types stay CallAgentIntent and OpenAgentChatIntent, and Open Chat's parameter is still called bot. Only the title changed and the parameter's type widened to bots and groups. A bot's ID in the new conversation entity matches its BotEntity ID (hubKey/conversationID). Call Agent is unchanged.
• The intents now live in the app bundle instead of the widget extension. App Intents identifies an action by its app and type name, so existing shortcuts should still resolve. A shortcut that saved a bot for Open Chat with Agent might lose it, because the parameter's entity type changed. In that case it asks for the bot when it runs.
• On the iPhone, Call Agent and Open Chat leave their parameter optional, as before, so a shortcut can ask for the bot each time it runs. On the Mac the parameters are required, and that also prompts when they are left empty.

Tests:

• Mac: ShortcutActionTests passes (5 tests).
• iPhone: new HubChatsTests.shortcutsOpenAndSendToBotsAndGroups. It failed to compile before the change. After the change it compiles with build-for-testing, but it can't run on this Mac because there is no signing, so CI runs it. The built app's App Intents metadata lists the three actions and their phrases.

Fixes #153