chore: configure mise pre-commit checks

Add formatting, lint, and test tasks with Tombi, rustfmt, and Clippy configuration. Require agents to pass the pre-commit task before committing.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

AGENTS.md

@@ -45,12 +45,16 @@ proposed capabilities as plans, not existing behavior.
 Run these from the repository root:
 
 ```sh
-cargo fmt --all -- --check
+mise run format
-cargo check --workspace
+mise run lint
-cargo clippy --workspace --all-targets -- -D warnings
+mise run test
-cargo test --workspace
+mise run pre-commit
 ```
 
+`mise run pre-commit` runs format, lint, and test sequentially, stopping on
+failure. Formatting uses the repository's Tombi and rustfmt configurations.
+Clippy checks all workspace targets and treats warnings as errors.
+
 The current project is a minimal executable and may not yet have tests.
 
 ## Conventions
@@ -63,5 +67,9 @@ The current project is a minimal executable and may not yet have tests.
 - Do not push changes unless explicitly asked.
 - Check the current branch before committing. Use conventional commit messages
   and include the repository's configured Copilot co-author trailer.
-- Run relevant formatting, build, lint, and test checks before committing code
+- Before every commit, including documentation-only commits, run
-  changes. Documentation-only changes do not require code checks.
+  `mise run pre-commit` and require a successful exit. Fix all reported
+  formatting, lint, and test problems, then rerun the task until it passes.
+  Do not bypass checks or suppress diagnostics merely to make a commit pass.
+- Review and stage formatter changes before committing. If further changes
+  are made after validation, rerun `mise run pre-commit` before committing.

Cargo.toml

@@ -1,5 +1,6 @@
 [workspace]
 resolver = "3"
 members = [
-    "crates/runa", "crates/runa-rune",
+    "crates/runa",
+    "crates/runa-rune",
 ]

README.md

@@ -41,6 +41,26 @@ cargo run -p runa
 
 At this stage, it prints `Hello, world!`.
 
+## Development
+
+Install [mise](https://mise.jdx.dev/) and run `mise install` to install Tombi.
+Rust, rustfmt, and Clippy must also be available on your PATH.
+
+```sh
+mise run format
+mise run lint
+mise run test
+mise run pre-commit
+```
+
+The pre-commit task runs formatting, linting, and tests in that order, stopping
+on the first failure. Run it successfully before committing and review any
+formatter changes. This is a task, not an automatically installed Git hook.
+
+Tombi formats TOML files offline; rustfmt formats all workspace Rust code.
+Clippy checks all workspace targets with warnings treated as errors, and the
+test task runs `cargo test --workspace`.
+
 ## Project structure
 
 ```text

clippy.toml

@@ -0,0 +1 @@
+doc-valid-idents = ["..", "Runa", "Rune"]

mise.toml

@@ -0,0 +1,18 @@
+[tools]
+tombi = "latest"
+
+[tasks.format]
+description = "Format TOML and Rust files"
+run = ["tombi format --offline", "cargo fmt --all"]
+
+[tasks.test]
+description = "Run workspace tests"
+run = "cargo test --workspace"
+
+[tasks.lint]
+description = "Lint all workspace targets with Clippy"
+run = "cargo clippy --workspace --all-targets -- -D warnings"
+
+[tasks.pre-commit]
+description = "Format, lint, and test before committing"
+run = [{ task = "format" }, { task = "lint" }, { task = "test" }]

rustfmt.toml

@@ -0,0 +1,2 @@
+edition = "2024"
+style_edition = "2024"

tombi.toml

@@ -0,0 +1,9 @@
+[files]
+include = ["**/*.toml"]
+exclude = ["target/**"]
+
+[format.rules]
+indent-style = "space"
+indent-width = 4
+line-ending = "lf"
+line-width = 100