feat(project): the project-as-crate load boundary (cycle 0102)

A research project is now a loadable external cdylib crate. Inside a
directory whose ancestry holds an Aura.toml, aura discovers the project
root cargo-style, locates the compiled dylib via cargo metadata (debug
default, --release opt-in), loads it load-and-hold, and refuses
mismatches before trusting anything: the AURA_PROJECT descriptor
(aura-core::project, #[repr(C)]) carries a C-ABI stamp prefix (rustc +
aura-core version, baked per consuming build by the new aura-core
build.rs) validated before any Rust-ABI field is read. The vocabulary
charter gates the merged resolution: project type ids are ::-namespaced
(std stays bare), duplicates refuse, and the enumerable type-id list
must agree with the resolver, so introspection can never silently omit
a project type.

All blueprint verbs resolve through the merged project + std vocabulary
via a per-invocation Env threaded through the dispatch chains;
registry, trace-store, and data paths anchor at the project runs root
(Aura.toml [paths], paths-only by design — instrument geometry stays
the recorded sidecar, C15). RunManifest gains the Tier-1 project
provenance field (namespace + dylib sha256 + best-effort commit),
stamped beside topology_hash on the blueprint-run paths; pre-0102
registry lines load unchanged. Default node names strip the namespace,
so :: never reaches the param-path address space.

Proven by the demo-project fixture (built by the e2e via cargo,
path-dep on this workspace): run twice bit-identical, provenance
recorded, introspection lists demo::* beside std, registry anchors at
the discovered root from a subdirectory; the badcharter fixture proves
the charter refusal through the real libloading path; a never-built
project refuses with a cargo-build hint. Outside a project every path
collapses to the previous literals — goldens and manifest pins
byte-identical.

Verification: cargo build --workspace clean; cargo test --workspace 862
passed / 0 failed (incl. 7 project_load e2e); clippy -D warnings clean
(one precedent-matching allow(too_many_arguments) on run_oos_blueprint,
whose arity the Env threading raised to 8); doc build unchanged.
Docs/ledger aligned: Aura.toml field lists are paths-only in
project-layout.md, glossary, C16/C17; new C13 realization note records
the per-invocation-reload reading and the load-and-hold one-shot scope
boundary.

New deps, per-case review (aura-cli leaf binary only, never the frozen
artifact): libloading, toml.

refs #180

Cargo.lock

@@ -118,9 +118,11 @@ dependencies = [
  "clap",
  "data-server",
  "libc",
+ "libloading",
  "serde",
  "serde_json",
  "sha2",
+ "toml",
 ]
 
 [[package]]
@@ -622,6 +624,16 @@ version = "0.2.186"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "68ab91017fe16c622486840e4c83c9a37afeff978bd239b5293d61ece587de66"
 
+[[package]]
+name = "libloading"
+version = "0.8.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d7c4b02199fee7c5d21a5ae7d8cfa79a6ef5bb2fc834d6e9058e89c825efdc55"
+dependencies = [
+ "cfg-if",
+ "windows-link",
+]
+
 [[package]]
 name = "log"
 version = "0.4.32"
@@ -840,6 +852,15 @@ dependencies = [
  "zmij",
 ]
 
+[[package]]
+name = "serde_spanned"
+version = "0.6.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bf41e0cfaf7226dca15e8197172c295a782857fcb97fad1808a166870dee75a3"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "sha1"
 version = "0.10.6"
@@ -948,6 +969,47 @@ version = "0.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7694e1cfe791f8d31026952abf09c69ca6f6fa4e1a1229e18988f06a04a12dca"
 
+[[package]]
+name = "toml"
+version = "0.8.23"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dc1beb996b9d83529a9e75c17a1686767d148d70663143c7854d8b4a09ced362"
+dependencies = [
+ "serde",
+ "serde_spanned",
+ "toml_datetime",
+ "toml_edit",
+]
+
+[[package]]
+name = "toml_datetime"
+version = "0.6.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "22cddaf88f4fbc13c51aebbf5f8eceb5c7c5a9da2ac40a13519eb5b0a0e8f11c"
+dependencies = [
+ "serde",
+]
+
+[[package]]
+name = "toml_edit"
+version = "0.22.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "41fe8c660ae4257887cf66394862d21dbca4a6ddd26f04a3560410406a2f819a"
+dependencies = [
+ "indexmap",
+ "serde",
+ "serde_spanned",
+ "toml_datetime",
+ "toml_write",
+ "winnow",
+]
+
+[[package]]
+name = "toml_write"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5d99f8c9a7727884afe522e9bd5edbfc91a3312b36a77b5fb8926e4c31a41801"
+
 [[package]]
 name = "typenum"
 version = "1.20.1"
@@ -1094,6 +1156,15 @@ dependencies = [
  "windows-link",
 ]
 
+[[package]]
+name = "winnow"
+version = "0.7.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "df79d97927682d2fd8adb29682d1140b343be4ac0f08fd68b7765d9c059d3945"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "wit-bindgen"
 version = "0.57.1"