Add ghcide configuration files

This commit adds three new files

1. A hie.yaml file to the project root which specifies to IDEs how to
set up the correct environment for loading GHC. This currently
specifies to call the `./hadrian/hie-bios` script.
2. A `hie.yaml` file for the hadrian subcomponent, which uses the
`cabal` cradle type.
2. The `./hadrian/hie-bios` script which supplies the correct arguments
for an IDE to start a session.

With these two files it is possible to run

```
ghcide compiler/
```

and successfully load all the modules for use in the IDE.

or

```
ghcide --cwd hadrian/ src/
```

to test loading all of Hadrian's modules.

Closes #17194

1 files changed, 5 insertions, 0 deletions

diff --git a/hie.yaml b/hie.yaml
new file mode 100644
index 0000000000..d23f66c1c4
--- /dev/null
+++ b/hie.yaml
@@ -0,0 +1,5 @@
+# This is a IDE configuration file which tells IDEs such as `ghcide` how
+# to set up a GHC API session for this project.
+#
+# The format is documented here - https://github.com/mpickering/hie-bios
+cradle: {bios: {program: "./hadrian/hie-bios"}}