Add a URI-like binary resolver, unit and integration tests

[buddhisthead]

This PR adds a URI-like binary resolver, whose primary use is to enable passing large chunks of data over the message bus by reference and hiding the implementation from the consumer. We anticipate it's use being first in the snapshot booting process where we pass chunks of blocks to the various state modules.

The binary URI-like API has a couple of initial formats including raw bytes and a file with offset and length. Usage is that a producer of the URI creates it with a unique ID and supplies a format enum. The consumer calls a global resolver which interprets the format enum and appropriately returns the bytes using a generic function signature, so new formats and resolver traits can be supplied in the future.

The PR contains unit and integration tests.

Running Tests

Unit tests:
cargo test -p acropolis_common --lib resolver::

Integration tests:

$ cargo test --test loc_over_bus -p acropolis_common

[Copilot]

Pull Request Overview

This PR introduces a URI-like binary resolver system to efficiently handle large data chunks over message buses. The primary purpose is to enable passing binary data by reference rather than by value, with initial use planned for the snapshot booting process.

Key changes:

• Added a new resolver module with Loc, Registry, and Resolver types for managing memory-mapped files and inline data
• Implemented comprehensive unit tests covering inline payloads, file-backed resolution, eviction, bounds checking, and concurrency
• Created integration tests demonstrating end-to-end usage over the Caryatid message bus

Reviewed Changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
common/src/resolver.rs	Core resolver implementation with Registry for memory-mapped files and Loc for uniform data location
common/src/lib.rs	Module declaration to expose the resolver module
common/Cargo.toml	Added dependencies for bytes, memmap2, tempfile, and test infrastructure
common/tests/loc_over_bus.rs	Integration test demonstrating Loc serialization and resolution over message bus
common/tests/test.toml	Configuration file for integration test environment

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[sandtreader]

Not sure if this is essential but we've managed to avoid any unsafe so far

[buddhisthead]

Good call. I'll clear that out.

[Quantumplation]

If we do end up needing unsafe, it's good practice to include a comment with every unsafe block explaining thoroughly why we, as humans, can be sure it's safe when the compiler cannot.

(unsafe is a bit of a poorly chosen word, IMO; it more so means that the compiler can't check the safety, and so the human must instead)