chore: move to One Big Cargo Workspace (#219)

This commit changes the Cargo workspace setup to put all crates in One
Big Workspace, rather than having separate workspaces for some targets.
We now use the `per-package-target` unstable cargo feature to build
different crates for different targets. This means that `cargo` commands
in the root workspace now work without requiring the user to `cd` into a
particular directory to build a platform target --- for example, I can
now run:

```shell
# in the repo root directory
$ cargo build -p mnemos-d1 --bin mq-pro
```

and build a MnemOS binary for the MQ Pro, without having to `cd` into
the MQ Pro directory.

This is also necessary in order to make the `x86_64` build process added
in PR #216 work, since it relies on cargo artifact dependencies, which
appear not to work across workspaces.

One issue is that `cargo build --workspace` (and `check --workspace`,
etc) still does not work correctly, due to some [weird][1] [issues][2]
with feature unification which I don't entirely understand. However, as
a workaround, I've changed the workspace Cargo.toml to add a
[`default-members` field][3], so that running `cargo build` or `cargo
check`
_without_ `--workspace` will build the subset of crates in the
`default-members` key. This way, `cargo {build, check, etc}` in the repo
root will do something reasonable by default, and the actual platform
targets can be built/checked with `cargo $WHATEVER --package $CRATE`.
IMO, this is still substantially nicer than having a bunch of separate
workspaces.

[1]: ia0/data-encoding#47
[2]: bincode-org/bincode#556
[3]: https://doc.rust-lang.org/cargo/reference/workspaces.html#the-default-members-field

.cargo/config.toml

@@ -1,3 +1,12 @@
+[alias]
+crowtty = "run --bin crowtty --release --"
+melpomene = "run --bin melpomene --release --"
+melpo = "melpomene"
+forth3 = "run --bin f3repl --release --"
+
 [build]
 # Currently needed for `tokio-console` support.
-rustflags = ["--cfg", "tokio_unstable"]
+rustflags = ["--cfg", "tokio_unstable"]
+
+[target.riscv32imac-unknown-none-elf]
+runner = "espflash flash --monitor"

.github/workflows/ci.yml

@@ -136,14 +136,6 @@ jobs:
       run: rustup show
     - uses: actions/checkout@v2
     - uses: olix0r/cargo-action-fmt@ee1ef42932e44794821dab57ef1bf7a73df8b21f
+    - uses: extractions/setup-just@v1
     - name: run rustdoc
-      run: |
-        cargo doc \
-          --message-format=json \
-          --no-deps \
-          --all-features \
-          --workspace \
-          --document-private-items |
-          cargo-action-fmt
-      env:
-        RUSTDOCFLAGS: "--cfg docsrs -Dwarnings"
+      run: just docs --message-format=json --document-private-items

.vscode/settings.json

@@ -0,0 +1,20 @@
+{
+    "rust-analyzer.check.invocationLocation": "workspace",
+    "rust-analyzer.cargo.buildScripts.invocationLocation": "workspace",
+    "rust-analyzer.cargo.buildScripts.overrideCommand": [
+        "cargo",
+        "check",
+        "--quiet",
+        "--message-format=json",
+        "--all-targets"
+    ],
+    "rust-analyzer.check.overrideCommand": [
+        "cargo",
+        "clippy",
+        "--quiet",
+        "--message-format=json",
+        "--all-targets"
+    ],
+    "rust-analyzer.workspace.symbol.search.scope": "workspace_and_dependencies",
+    "rust-analyzer.typing.continueCommentsOnNewline": false
+}