crate-init: crate skeleton — module map, feature gates, TlsError, re-export block deferred per port

- src/lib.rs: crate docs, ADR-002 TlsError verbatim (six variants,
  #[non_exhaustive], typed #[source] chains), module declarations,
  compile-assertion tests for the enum + noq-gated NoqWrap
- seven module files with doc headers only (ports land per task)
- Cargo.toml verified against ADR-003 verbatim (no edits needed)
- deviation: VerifierBuild source is rustls::client::VerifierBuilderError
  (rustls::webpki is private at pinned 0.23.44; same type, public path)

Verification: cargo build/test (default, noq, tcp, acme, all-features),
clippy -D warnings, fmt --check, doc --no-deps — all green

src/client.rs

@@ -0,0 +1,4 @@
+//! Client-side TLS configuration: [`TlsClientConfig`],
+//! [`FingerprintPinVerifier`], [`RawKeyClientCertResolver`],
+//! [`NoClientCertResolver`], [`select_server_verifier`],
+//! [`build_client_auth`], [`load_platform_root_cert_store`].

src/credentials.rs

@@ -0,0 +1,3 @@
+//! Transport-level credential bundle for outbound connections:
+//! [`ConnectionCredentials`], [`RemoteIdentity`] (ADR-005, moved from
+//! alknet-core `credentials.rs`).

src/fingerprint.rs

@@ -0,0 +1,10 @@
+//! TLS certificate fingerprint extraction: [`fingerprint_from_cert_der`],
+//! [`extract_ed25519_raw_key_from_spki`], and the private manual DER parser
+//! (ADR-005, moved from alknet-core).
+//!
+//! Fingerprint formats (alknet ADR-030 §6):
+//!
+//! - **Ed25519 raw key** (RFC 7250 SPKI): `ed25519:<hex of 32-byte pub key>`
+//!   — the fingerprint IS the trust anchor.
+//! - **X.509 cert**: `SHA256:<hex of DER>` — the fallback for everything
+//!   else.

src/identity.rs

@@ -0,0 +1,2 @@
+//! Identity types: [`TlsIdentity`], [`Ed25519SecretKey`], [`AcmeDirectory`]
+//! (ADR-005, moved from alknet-core `config.rs`).

src/lib.rs

@@ -1,27 +1,103 @@
-//! alktls: shared TLS setup types — server and client rustls configs,
-//! cert resolvers, verifiers, and shared signing helpers.
+//! alktls: shared TLS setup types — server and client `rustls` configs,
+//! cert resolvers, verifiers, ACME state-machine wiring, and the identity /
+//! credential / fingerprint types that drive config construction.
 //!
-//! Phase 0 (exploration) — the crate shape is being established in
-//! `docs/research/phase-0.md`. This placeholder keeps the scaffold
-//! building until the crate skeleton lands in Phase 1.
+//! The crate owns **config construction**: given an identity and an ALPN
+//! list, produce a `rustls::ServerConfig` or `rustls::ClientConfig` and hand
+//! it to whichever transport wrapper the deployment runs (`noq` for QUIC,
+//! `tokio-rustls` for TCP+TLS). It does not dial, accept, dispatch, or
+//! resolve peer identities — those belong to the dial seam, the accept
+//! loop, and the auth layer.
+//!
+//! Core types:
+//!
+//! - [`TlsServerConfig`] — built once per identity + ALPN list, shared
+//!   across transports via [`Arc`](std::sync::Arc) (not `Clone`; it holds
+//!   the ACME task's `JoinHandle`).
+//! - [`TlsClientConfig`] — built per dial from a [`ConnectionCredentials`] +
+//!   ALPN; consumed by its accessors.
+//! - [`TlsError`] — the config-construction error type. Handshake outcomes
+//!   and ACME runtime errors are not `TlsError`s.
+//!
+//! Transport-specific accessors are feature-gated: `noq` (`for_noq`),
+//! `tcp` (`for_tcp_tls`), `acme` (the ACME path). `default = []`.
+
+pub mod client;
+pub mod credentials;
+pub mod fingerprint;
+pub mod identity;
+pub mod pem;
+pub mod server;
+pub mod signing;
+
+// The re-export block (the documented public API surface) lands per
+// module as each port task completes; the final shape is ADR-006's
+// module map + overview.md §What the crate is.
 
 #[derive(Debug, thiserror::Error)]
+#[non_exhaustive]
 pub enum TlsError {
+    /// Cert or key file read / PEM parse. `rustls_pemfile` funnels its
+    /// own error type into `io::Error`, so one `io::Error` source covers
+    /// the whole loading path.
+    #[error("loading cert/key material: {0}")]
+    CertLoad(#[from] std::io::Error),
+
+    /// Self-signed cert generation (rcgen). Server `SelfSigned` path.
+    #[error("generating self-signed cert: {0}")]
+    SelfSigned(#[from] rcgen::Error),
+
+    /// rustls server or client config construction
+    /// (`with_safe_default_protocol_versions`, `with_single_cert`,
+    /// `CertifiedKey::from_der`, `RootCertStore::add`).
+    #[error("building rustls config: {0}")]
+    Rustls(#[from] rustls::Error),
+
+    /// `WebPkiServerVerifier::builder(_with_provider)..build()` — the
+    /// unknown-X.509-remote client path. Re-exported by rustls at
+    /// `rustls::client` (the `rustls::webpki` module is private at the
+    /// pinned 0.23.44; same type, public path).
+    #[error("building webpki verifier: {0}")]
+    VerifierBuild(#[from] rustls::client::VerifierBuilderError),
+
+    /// QUIC config wrapping — the one path where `for_noq()` fails
+    /// (`NoInitialCipherSuite`, not a `rustls::Error`). noq-gated.
+    #[cfg(feature = "noq")]
+    #[error("wrapping rustls config for noq: {0}")]
+    NoqWrap(#[from] noq_proto::crypto::rustls::NoInitialCipherSuite),
+
+    /// Config-mismatch errors that are not wrapped third-party
+    /// errors: ACME feature not enabled but `Acme` configured
+    /// (server), or `Acme` identity used for client auth. A config
+    /// error, not a wrapped third-party error.
     #[error("TLS config error: {0}")]
-    Config(String),
-    #[error("I/O error: {0}")]
-    Io(#[from] std::io::Error),
-    #[error("certificate error: {0}")]
-    Cert(String),
+    AcmeConfig(String),
 }
 
 #[cfg(test)]
 mod tests {
-    use super::*;
+    use super::TlsError;
 
     #[test]
-    fn error_type_constructs() {
-        let e = TlsError::Config("placeholder".into());
-        assert!(e.to_string().contains("placeholder"));
+    fn tls_error_matches_the_adr_002_variant_set() {
+        let io: TlsError = std::io::Error::other("x").into();
+        assert!(matches!(io, TlsError::CertLoad(_)));
+        let rcgen: TlsError = rcgen::Error::CouldNotParseCertificate.into();
+        assert!(matches!(rcgen, TlsError::SelfSigned(_)));
+        let rustls: TlsError = rustls::Error::General("x".into()).into();
+        assert!(matches!(rustls, TlsError::Rustls(_)));
+        let builder: TlsError = rustls::client::VerifierBuilderError::NoRootAnchors.into();
+        assert!(matches!(builder, TlsError::VerifierBuild(_)));
+        let acme = TlsError::AcmeConfig("acme feature not enabled".into());
+        assert!(acme.to_string().contains("acme feature not enabled"));
+    }
+
+    #[cfg(feature = "noq")]
+    #[test]
+    fn tls_error_noq_wrap_variant_exists() {
+        let _ = matches!(
+            Option::<TlsError>::None,
+            Some(TlsError::NoqWrap(_)) | Some(_)
+        );
     }
 }

src/pem.rs

@@ -0,0 +1,2 @@
+//! PEM loading helpers: [`load_cert_chain`], [`load_private_key`].
+//! One copy used by both server and client.

src/server.rs

@@ -0,0 +1,3 @@
+//! Server-side TLS configuration: [`TlsServerConfig`],
+//! [`RawKeyCertResolver`], [`AcceptAnyCertVerifier`], [`SelfSignedCert`],
+//! [`generate_self_signed_cert`], and the ACME path (feature `acme`).

src/signing.rs

@@ -0,0 +1,3 @@
+//! Ed25519 signing key usable as both a rustls `SigningKey` and `Signer`:
+//! [`Ed25519SigningKey`]. One copy used by both server
+//! (`RawKeyCertResolver`) and client (`RawKeyClientCertResolver`).

tasks/crate-init.md

@@ -1,7 +1,7 @@
 ---
 id: crate-init
 name: Crate skeleton — module files, feature gates, error type, re-exports
-status: pending
+status: completed
 depends_on: []
 scope: narrow
 risk: low
@@ -77,7 +77,59 @@ land now so subsequent tasks are additive, not structural.
 > Agent fills this during implementation. Document any decisions,
 > deviations from architecture, or relevant context discovered.
 
+### Decisions / deviations
+
+1. **`VerifierBuild` source path: `rustls::client::VerifierBuilderError`,
+   not `rustls::webpki::VerifierBuilderError`.** The ADR-002 sketch used
+   the `rustls::webpki` path, but at the pinned rustls 0.23.44 that
+   module is private — the type is re-exported publicly at
+   `rustls::client` (verified in the 0.23.44 source: `mod webpki;` +
+   `pub use crate::webpki::{VerifierBuilderError, ...}` inside
+   `pub mod client`). Same type, public path; noted in the variant's
+   doc comment. ADR-002 needs a one-line amendment (recorded for the
+   review-impl docs-sync pass).
+2. **Re-export block deferred per module.** `lib.rs` carries the module
+   declarations now; the `pub use` block lands incrementally with each
+   port task (a re-export of a not-yet-ported type cannot compile, and
+   every intermediate commit must stay green). The final shape is
+   ADR-006's map + overview.md's surface; port-client (the last module
+   port) completes it.
+3. **The `noq`-gated compile assertion** cannot construct
+   `NoInitialCipherSuite` from outside noq-proto (private field), so the
+   test is an existence proof via `matches!` on `Option<TlsError>` —
+   compiles only when the variant + its `#[from]` source exist.
+4. **`Cargo.toml` unchanged** — the scaffold's TOML already matched
+   ADR-003's block exactly (features `default = []` / `noq` / `tcp` /
+   `acme`; `noq` with `default-features = false, features = ["rustls"]`).
+   Verified against ADR-003 line-by-line; no edits needed.
+
 ## Summary
 
 > Agent fills this on completion. Brief description of what was
-> implemented, files changed, and any follow-up needed.
+> implemented, files changed, and any follow-up needed.
+
+### What landed
+
+- `src/lib.rs`: crate docs + the ADR-002 `TlsError` verbatim (six
+  variants, `#[non_exhaustive]`, `#[source]` chains; `NoqWrap`
+  noq-gated) + module declarations + a compile-assertion test for the
+  enum (`#[from]` conversions + `AcmeConfig` display) and the noq-gated
+  `NoqWrap` existence test.
+- The seven module files (`identity`, `credentials`, `fingerprint`,
+  `server`, `client`, `pem`, `signing`) with `//!` doc headers only —
+  no bodies, per "what does NOT land here".
+- Feature matrix verified: default, `noq`, `tcp`, `acme`,
+  `--all-features`.
+
+### Verification
+
+- `cargo build` (default) ✓; `cargo test` ✓ (1 test);
+  `cargo test --features noq` ✓ (2 tests); `cargo check --features
+  tcp|acme` ✓; `cargo test --all-features` ✓; `cargo clippy
+  --all-targets --all-features -- -D warnings` ✓; `cargo fmt --check` ✓;
+  `cargo doc --no-deps` ✓.
+
+### Follow-up
+
+- ADR-002 amendment note for the `VerifierBuilderError` path
+  (review-impl docs sync).