Plug-ins: the texts say a grant accepted under the flag stays recorded

A grant accepted under --allow-plugin-grants is written to grants.json like a
person's approval and counts as approved in later sessions and in the desktop
app. The CLI usage text, the plugin.install params text and docs/plugins.md and
docs/mcp.md said only a person's approval in the desktop app records one.

docs/plugins.md

@@ -30,7 +30,7 @@ This page is the contract for plug-in authors and the reference for the host (`c
 | `plugin.list` | `{}` | `{"plugins": [{id, name, version, kind, author, description, params, paramsSchema, effect?, format?, extensions?, budget?, commands?, size, source, api, paintOutput?, permissions, hash, cacheBytes}], "folder": report}` (`api` is the manifest's [plug-in API level](#permissions); `budget: "heavy"` for a [heavy filter](#heavy-filters); `commands` lists its [commands](#commands); `paintOutput: true` marks a [painted live effect](#painted-live-effects); `permissions` lists what it [may do](#permissions), `hash` is the module's SHA-256; `cacheBytes` is the size of its [cache](#settings-and-cache)) |
 | `plugin.info` | `{"id"}` | One plug-in: the `plugin.list` entry plus `manifest`, `defaults` and `lastError` (a live effect's last failure). |
 | `plugin.run` | `{"id", "params"?: {…}, "ids"?: [...]}` (plug-in params may also be top-level keys) | Runs an object filter on the selection (or `ids`; an `ids` that is not a list of object ids is an error). One undo step; the result is selected, except the objects it locked or made guides. |
-| `plugin.install` | `{"path": "/x/y.wasm"}` (desktop) or `{"dataBase64": "…", "name"?}`, `"replace"?: bool`, `"allowHeavy": bool = false`, `"grant"?: [permission]`, `"hash"?: "sha256 hex"` | Validates and installs a module; returns its `plugin.list` entry. The desktop app and `vectorcraft-cli` keep it in the `Plug-ins` folder next to the preferences, so it is installed again after a restart (#2541). A module with other bytes than the plug-in installed with its id, or, with none installed, one whose id has [settings and a cache](#settings-and-cache) in the `Plug-ins` folder, installs only with `replace: true`, once the user agreed; it takes that plug-in's place and gets its settings and cache. The same module installs again without `replace`, and `replace: false` refuses a module whose id is installed. A [heavy filter](#heavy-filters) installs only with `allowHeavy: true`. A plug-in whose manifest lists [permissions](#permissions) installs only when `grant` lists every one of them, unless a person already granted a module with the same SHA-256. A request's `grant` and `allowHeavy` are refused except in a session started with `vectorcraft-cli --allow-plugin-grants`. With `hash`, a module whose SHA-256 differs is refused. |
+| `plugin.install` | `{"path": "/x/y.wasm"}` (desktop) or `{"dataBase64": "…", "name"?}`, `"replace"?: bool`, `"allowHeavy": bool = false`, `"grant"?: [permission]`, `"hash"?: "sha256 hex"` | Validates and installs a module; returns its `plugin.list` entry. The desktop app and `vectorcraft-cli` keep it in the `Plug-ins` folder next to the preferences, so it is installed again after a restart (#2541). A module with other bytes than the plug-in installed with its id, or, with none installed, one whose id has [settings and a cache](#settings-and-cache) in the `Plug-ins` folder, installs only with `replace: true`, once the user agreed; it takes that plug-in's place and gets its settings and cache. The same module installs again without `replace`, and `replace: false` refuses a module whose id is installed. A [heavy filter](#heavy-filters) installs only with `allowHeavy: true`. A plug-in whose manifest lists [permissions](#permissions) installs only when `grant` lists every one of them, unless a grant is already recorded for a module with the same SHA-256. A request's `grant` and `allowHeavy` are refused except in a session started with `vectorcraft-cli --allow-plugin-grants`. With `hash`, a module whose SHA-256 differs is refused. |
 | `plugin.inspect` | as `plugin.install`: `{"path"}` or `{"dataBase64", "name"?}` | Validates a module without installing it; returns the `plugin.list` entry it would have, plus `needsApproval` (true when installing it needs a person's approval) and `needsReplace` (true when `plugin.install` needs `replace: true`). |
 | `plugin.remove` | `{"id"}` | Uninstalls, and deletes it from the `Plug-ins` folder with its [settings and cache](#settings-and-cache). |
 | `plugin.clearCache` | `{"id"?}` | Deletes every entry in the [cache](#settings-and-cache) of plug-in `id`, or of every installed plug-in; settings stay. Returns `{"cleared": [id], "bytesFreed"}`. |
@@ -198,12 +198,14 @@ capability model proposed for PhotoCraft plug-ins
   Only a person can press its OK: `ui.dialog.confirm`, MCP's `answer_dialog` and injected input (`ui.key`, `ui.click`)
   are refused and the dialog stays open. Enter confirms it only when OK has the keyboard focus. `ui.dialog.set` can't
   change what it installs.
-- `plugin.install` refuses the module, naming the permissions it needs, unless a person already granted this module
+- `plugin.install` refuses the module, naming the permissions it needs, unless this module already has a recorded grant
   (`plugin.inspect`'s `needsApproval` tells it beforehand). A request's `grant` is refused too: `plugin.install` takes
   it only with the approval the dialog gives. A `vectorcraft-cli mcp` or `run` started with `--allow-plugin-grants`
   takes `grant` and `allowHeavy` from any request; only the person starting the process can set that flag, and it
   doesn't apply to a running app. Without it, MCP in headless mode and the CLI install a module that lists
-  permissions only when a person approved its hash in the desktop app, which they read from the shared `grants.json`.
+  permissions only when its hash is recorded in the shared `grants.json`. A person's approval in the desktop app
+  records it, and so does a `grant` accepted under `--allow-plugin-grants`. A recorded grant counts as approved in
+  later sessions without the flag and in the desktop app.
   With `--allow-plugin-grants`, pass `hash` set to the `plugin.inspect` entry's `hash` so that the module installed is
   the one the user saw.
 - **Replacing asks first.** When the file is another module than the plug-in installed with its id, or, with none