docs: add AGENTS.md and update CONTRIBUTING.md with commit conventions

Add CLI-specific AGENTS.md covering architecture, coding conventions,
conventional commit format, and release workflow. Update CONTRIBUTING.md
with accurate commit message and release documentation.

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

Author: Starefossen

AGENTS.md

@@ -0,0 +1,66 @@
+# AGENTS.md — cnctl CLI
+
+Instructions for AI coding agents working on the `cnctl` CLI.
+
+## Project
+
+Rust CLI (`cnctl`) for managing Cloud Native Days Norway conferences.
+Standalone Cargo project inside `cli/` of the main website monorepo.
+
+## Build & Test
+
+```sh
+mise run check          # clippy + fmt-check + test (parallel)
+mise run clippy         # pedantic lints, warnings as errors
+mise run fmt            # format with rustfmt
+mise run test           # all tests (unit + E2E)
+cargo test              # alternative without mise
+```
+
+## Architecture
+
+- **Commands** live in `src/commands/<domain>/` as multi-file modules (`mod.rs`, `args.rs`, `interactive.rs`, etc.)
+- **Types** live in `src/types/` — one file per API domain, re-exported from `mod.rs`
+- **Client** (`src/client.rs`) — tRPC HTTP client, all API calls go through here
+- **Display** (`src/display/`) — terminal rendering, table formatting, colors
+- **Template** (`src/template.rs`) — `{{{VAR}}}` substitution engine
+- Keep commands thin: API calls in `mod.rs`, display logic in `display/`, business logic in domain modules
+
+## Coding Conventions
+
+- Clippy pedantic enabled — no warnings allowed
+- Serde: `#[serde(rename_all = "camelCase")]`, `#[serde(rename = "_id")]`, `#[serde(default)]`
+- Unknown enum variants: `#[serde(other)] Unknown` with custom `Deserialize` + `Default` impls
+- Error handling: return `anyhow::Result<T>`, avoid `unwrap()` / `process::exit()`
+- Tests: unit tests in `#[cfg(test)]` modules, E2E tests in `tests/e2e.rs` using wiremock
+
+## Commit Messages & Release Notes
+
+Release notes are **auto-generated** from commit messages using [git-cliff](https://git-cliff.org/) (configured in `cliff.toml`).
+
+**All commits must use [Conventional Commits](https://www.conventionalcommits.org/) format:**
+
+- `feat:` / `feat(scope):` — new features (included in release notes)
+- `fix:` — bug fixes (included)
+- `perf:` — performance improvements (included)
+- `refactor:` — code refactoring (included)
+- `docs:` — documentation changes (included)
+- `chore:`, `style:`, `ci:`, `test:`, `build(deps):` — excluded from release notes
+
+Examples:
+```
+feat(sponsors): add email functionality with template support
+fix: handle missing conference ID in sponsor lookup
+refactor: extract shared email builder into helper module
+```
+
+## Releases
+
+Releases are fully automated via GitHub Actions:
+
+1. Push to `main` triggers CI (`ci.yml`: clippy, fmt, test on Linux/macOS/Windows)
+2. On CI success, release workflow (`release.yml`) cross-compiles for 5 targets
+3. git-cliff generates release notes from commits since the last tag
+4. A GitHub Release is created with binaries, checksums, and build provenance attestations
+
+Tags use date-based versioning: `YYYY.MM.DD-<shortsha>`. Do **not** create tags manually — the release workflow handles this.

CONTRIBUTING.md

@@ -30,15 +30,19 @@ Thanks for your interest in contributing to cnctl!
 
 ## Commit messages
 
-Use clear, concise commit messages. Reference issues where applicable.
+Use [Conventional Commits](https://www.conventionalcommits.org/) format.
+Release notes are auto-generated from these by git-cliff.
 
-## Releases
+```
+feat(sponsors): add email template picker
+fix: handle missing conference ID
+docs: update README with new flags
+```
 
-Releases are automated via GitHub Actions. Tag a version to trigger a build:
+See `cliff.toml` for which prefixes are included/excluded.
 
-```sh
-git tag v0.1.0
-git push origin v0.1.0
-```
+## Releases
 
-This cross-compiles binaries for Linux, macOS, and Windows.
+Releases are fully automated. Every push to `main` that passes CI triggers a
+release with cross-compiled binaries and auto-generated release notes. Tags use
+date-based versioning (`YYYY.MM.DD-<shortsha>`) — do not create tags manually.