docs(cli): document gnd delegation switchover

Add a changeset describing the major-version bump, document the new
gnd dispatch in the CLI README (including the GRAPH_CLI_IGNORE_GND
escape hatch and the removal of `graph node install`), add `graph
dev` to the command list, and mark `graph local` as deprecated in
favor of `graph dev`.

Author: lutter

.changeset/delegate-to-gnd.md

@@ -0,0 +1,20 @@
+---
+'@graphprotocol/graph-cli': major
+---
+
+Delegate commands to `gnd` by default
+
+`graph <cmd>` now execs the `@graphprotocol/gnd` binary (shipped as a
+dependency) instead of running the bundled TypeScript implementation.
+Set `GRAPH_CLI_IGNORE_GND=1` to force every command back through the
+oclif/TS code path.
+
+Breaking changes:
+
+- The `graph node install` command has been removed. Install `gnd` via
+  the `@graphprotocol/gnd` npm package instead — it is now a direct
+  dependency of `@graphprotocol/graph-cli` and no separate download
+  step is required.
+- `graph local` is the only command that still always runs the
+  TypeScript implementation; gnd has no equivalent.
+- `graph dev` is an oclif shim that always delegates to `gnd dev`.

packages/cli/README.md

@@ -17,13 +17,29 @@ As of today, the command line interface supports the following commands:
 - `graph auth` — Stores a [Graph Node](https://github.com/graphprotocol/graph-node) access token in
   the system's keychain.
 - `graph local` — Runs tests against a [Graph Node](https://github.com/graphprotocol/graph-node)
-  test environment (using Ganache by default).
+  test environment (using Ganache by default) (deprecated, use `graph dev` instead).
+- `graph dev` — Runs a local
+  [Graph Node](https://github.com/graphprotocol/graph-node) in dev mode (delegates to
+  [`gnd dev`](https://www.npmjs.com/package/@graphprotocol/gnd)).
 - `graph test` — Downloads and runs the [Matchstick](https://github.com/LimeChain/matchstick) rust
   binary in order to test a subgraph.
 - `graph add` - Adds a new datasource to the yaml file and writes the necessary changes to other
   files - schema.graphql, abi and mapping.
 - `graph publish` - Publishes the subgraph to the Graph Network.
 
+### Command dispatch via `gnd`
+
+By default, `graph <cmd>` execs the
+[`@graphprotocol/gnd`](https://www.npmjs.com/package/@graphprotocol/gnd) binary, which is shipped
+as a dependency of the CLI. The TypeScript implementation in this package is used as a fallback for
+commands that `gnd` does not provide.
+
+- `graph local` always runs the TypeScript implementation — `gnd` has no equivalent.
+- Set `GRAPH_CLI_IGNORE_GND=1` to route every command through the TypeScript implementation.
+
+The previous `graph node install` command, which downloaded a `gnd` binary from GitHub releases,
+has been removed. Installing `@graphprotocol/graph-cli` is now sufficient to get `gnd`.
+
 ## How It Works
 
 The Graph CLI takes a subgraph manifest (defaults to `subgraph.yaml`) with references to: